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Authigenic Gypsum in Gas-Hydrate Associated Sediments from the East Coast of India (Bay of Bengal)

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Acta Geologica Sinica(English Edition) 2013年第3期87卷 749-760页

作者： M. KOCHERLA national institute of oceanography

Authigenic gypsum crystals, along with pyrite and carbonate mineralization, predominantly calcites were noticed in distinct intervals in a 32 m long piston core, collected in the gas hydratebearing sediments in the northern portion of the Krishna-Godavari basin, eastern continental margin of India at a water depth of 1691 m. X-ray diffraction and energy dispersive spectrum studies confirm presence of pyrite, gypsum, calcite, and other mineral aggregates. The occurrence of gypsum in such deep sea environment is intriguing, because gypsum is a classical evaporite mineral and is under saturated with respect to sea water. Sedimentological, geochemical evidences point to diagenetic formation of the gypsum due to oxidation of sulphide minerals （i.e. pyrite）. Euhedral, transparent gypsum crystals, with pyrite inclusions are cemented with authigenic carbonates, possibly indicating that they were formed authigenically in situ in the gas hydrate-influenced environment due to late burial diagenesis involving sulphate reduction and anaerobic oxidation of methane （AOM）. Therefore, the authigenic gypsums found in sediments of the Krishna-Godavari and Mahanadi offshore regions could be seen as one of the parameters to imply the presence of high methane flux possibly from gas hydrate at depth.

关键词： authigenic gypsum pyrites gas-hydrates Krishna-Godavari and Mahanadi offshore Anaerobic Oxidation of Methane (AOM) Eastern continental margin of India

Macrobenthos monitoring in the Gulf of Suez,Egypt

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Acta Oceanologica Sinica 2008年第2期27卷 55-80页

作者： Mohamed M.El-Komi national institute of oceanography and Fisheries

The biogeography of macrobenthic communities with large-scale differences in species distribution and abundance was studied along the eastern and western coastal regions of the Gulf of Suez to indicate biodiversity of benthos in relation to the prevailing environmental conditions. In general, benthos have a wide variety of species of mainly polychaet worms, crustaceans, bivalves, and other bottom invertebrates living in burrows in/or on the sediment surface. Coastal development clearly affects the ecosystem after the construction of coastal projects. The highest values of benthic diversity, evenness, richness and dominance are found at the Gulf of Suez （WG 1, WG 3）, Ras Gharib （WG 7, WG 8） and Ras Shukier （WG 9a） by contrast to others. The abundance of macrobenthic organsims along the coasts of Gulf of Suez can be arranged in the following sequence： other groups （34%） greater than crustaceans （25%） greater than polychaetes （22%） greater than molluscs （17%） greater than echinoderms （2%）. The biomass of benthic assemblages at different sampling sites can also be ranked as follows： echinoderms （52%） greater than molluscs （27%） greater than crustaceans （16%） greater than polychaetes （2%） greater than other groups （3%）. Some benthic groups or species indicated a distinctive correlation to pollution sources in the marine ecosystem which obviously increased in the coastal areas due to the extension of the coastal development. These activities needed regular information to establish database for the biology and distribution of marine benthic communities. The density and diversity of benthos are significantly affected by eutrophication at Ain Sukhna, whereas the benthos in the open Gulf of Suez do not seem to be adversely affected by pollution.

关键词： macrobenthos assessment impact Gulf of Suez

How will Benthic Foraminifera Respond to Warming and Changes in Productivity ?: A Laboratory Culture Study on Cymbaloporetta plana

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Acta Geologica Sinica(English Edition) 2019年第1期93卷 175-182页

作者： KURTARKAR R.Sujata SARASWAT Rajeev KAITHWAR Amrata NIGAM Rajiv Micropaleontology Laboratory Geological Oceanography Division National Institute of Oceanography

Anthropogenic activities are likely to cause global warming. Global warming will affect marine productivityand thus food availability for marine organisms. Both the seawater temperature and food availability affect benthicforaminifera, the most abundant marine calcareous microorganisms. Therefore, a laboratory culture experiment wasconducted on Cymbaloporetta plana to understand the coupled effect of temperature(25°C, 27°C, 30°C) and food(102±5,203±9, 305±14, 407±18, 508±23 diatom cells). At all temperatures, growth increased with increase in food. The specimenssubjected to 27°C temperature attained the maximum growth and those subjected to 25°C were the smallest. All specimensfed with 508±23 cells reproduced, 0 irrespective of temperature. Of all the specimens without food, 40% at 27°C and 20% at25°C reproduced, whereas specimens subjected to 30°C did not reproduce. The 100% rate of reproduction at 27°C suggeststhat it is the optimum temperature for growth and reproduction. All the specimens at 30°C and without additional food,died, whereas at 25°C and 27°C, the mortality rate was 80% and 60%, respectively. The limited growth and reproductionwith decreasing food clearly indicates that food availability also controls the growth and reproduction of shallow waterbenthic foraminifer C. plana. Therefore, warming coupled with decreasing productivity is likely to severely affect thegrowth and abundance of shallow water benthic foraminifera.

关键词： Cymbaloporetta plana culture experiment temperature food reproduction

Does Glacial-Interglacial Transition Affect Sediment Accumulation in Monsoon-Dominated Regions?

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 1079-1094页

作者： Dharmendra Pratap SINGH Rajeev SARASWAT Dinesh K.NAIK Micropaleontology Laboratory Geological Oceanography DivisionNational Institute of Oceanography

The spatio-temporal changes in sedimentation rate along the continental margin of the monsoon-dominated eastern Arabian Sea during the last 24 kyr have been estimated from a compilation of 58 radiocarbon dated cores, in order to understand the effect of glacial-interglacial variation on sedimentation. The sedimentation rate has been computed for four-time slices, viz. the last glacial maximum, glacial-interglacial transition, early Holocene and late Holocene. We report that the average sedimentation rate in the slope to the abyssal region of the entire eastern Arabian Sea, although higher during the Holocene as compared with that during the last glacial maximum and glacial-interglacial transition, does not significantly vary during all four-time intervals. The sedimentation rate during any particular time interval, however, varies from core to core, thus indicating zonal changes. We report four zones of relatively high sedimentation rate, viz. the northeastern Arabian Sea, the region off the Gulf of Khambhat, the region off Goa and Mangalore, and off the southern tip of India. We suggest that a complex interaction of land-ocean-atmospheric processes controlled sedimentation rate in the eastern Arabian Sea during the last 24 kyr in such a way that the average sedimentation rate does not vary significantly, even during highly contrasting climatic conditions.

关键词： Sedimentation rate monsoon glacial Holocene Arabian Sea

Recovery of the injured neural system through gene delivery to surviving neurons in Parkinson’s disease

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Neural Regeneration Research 2025年第10期20卷 2855-2861页

作者： Chanchal Sharma Sehwan Kim Hyemi Eo Sang Ryong Kim School of Life Science Kyungpook National UniversityDaeguKorea BK21 FOUR KNU Creative BioResearch Group Kyungpook national University DaeguKorea Brain Science and Engineering institute Kyungpook National UniversityDaeguKorea

A critical unaddressed problem in Parkinson’s disease is the lack of therapy that slows or hampers *** medications effectively manage symptoms,they offer no long-term benefit because they fail to address the underlying neuronal *** highlights that the elusive goals of halting progression and restoring damaged neurons limit the long-term impact of current *** clinical trials using gene therapy have demonstrated the safety of various vector delivery systems,dosages,and transgenes expressed in the central nervous system,signifying tangible and substantial progress in applying gene therapy as a promising Parkinson’s disease ***,at diagnosis,many dopamine neurons remain in the substantia nigra,offering a potential window for recovery and *** propose that modulating these surviving dopamine neurons and axons in the substantia nigra and striatum using gene therapy offers a potentially more impactful therapeutic approach for future ***,innovative gene therapies that focus on preserving the remaining elements may have significant potential for enhancing long-term outcomes and the quality of life for patients with Parkinson’s *** this review,we provide a perspective on how gene therapy can protect vulnerable elements in the substantia nigra and striatum,offering a novel approach to addressing Parkinson’s disease at its core.

关键词： adeno-associated virus gene therapy neuroprotection neurorestoration neurotrophic factor nigrostriatal dopamine pathway pro-survival protein

Tower-Based Greenhouse Gas Measurement Network Design——The national institute of Standards and Technology North East Corridor Testbed

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Advances in Atmospheric Sciences 2017年第9期34卷 1095-1105页

作者： Israel LOPEZ-COTO Subhomoy GHOSH Kuldeep PRASAD James WHETSTONE national institute of Standards and Technology

The North-East Corridor （NEC） Testbed project is the 3rd of three NIST （national institute of Standards and Technology） greenhouse gas emissions testbeds designed to advance greenhouse gas measurements capabilities. A design approach for a dense observing network combined with atmospheric inversion methodologies is described. The Advanced Research Weather Research and Forecasting Model with the Stochastic Time-Inverted Lagrangian Transport model were used to derive the sensitivity of hypothetical observations to surface greenhouse gas emissions （footprints）. Unlike other network design algorithms, an iterative selection algorithm, based on a k-means clustering method, was applied to minimize the similarities between the temporal response of each site and maximize sensitivity to the urban emissions contribution. Once a network was selected, a synthetic inversion Bayesian Kalman filter was used to evaluate observing system performance. We present the performances of various measurement network configurations consisting of differing numbers of towers and tower locations. Results show that an overly spatially compact network has decreased spatial coverage, as the spatial information added per site is then suboptimal as to cover the largest possible area, whilst networks dispersed too broadly lose capabilities of constraining flux uncertainties. In addition, we explore the possibility of using a very high density network of lower cost and performance sensors characterized by larger uncertainties and temporal drift. Analysis convergence is faster with a large number of observing locations, reducing the response time of the filter. Larger uncertainties in the observations implies lower values of uncertainty reduction. On the other hand, the drift is a bias in nature, which is added to the observations and, therefore, biasing the retrieved fluxes.

关键词： greenhouse gases network design clustering analysis Kalman filter OSSE

Dysregulation of genes involved in the long-chain fatty acid transport in pancreatic ductal adenocarcinoma

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 199-206页

作者： Radu Cristian Poenaru Elena Milanesi Andrei Marian Niculae Anastasia-Maria Dobre Catalina Vladut Mihai Ciocîrlan Daniel Vasile Balaban Vlad Herlea Maria Dobre Mihail Eugen Hinescu Faculty of Medicine Carol Davila University of Medicine and PharmacyBucharest 050474Romania Department of Radiobiology Victor Babes National Institute of PathologyBucharest 050096Romania Department of Pathology Victor Babes National Institute of PathologyBucharest 050096Romania Department of Gastroenterology Prof.Dr.Agrippa Ionescu Clinical Emergency HospitalBucharest 011356Romania Department of Pathology Fundeni Clinical InstituteBucharest 022258Romania

BACKGROUND Pancreatic ductal adenocarcinoma(PDAC)is an aggressive lethal malignancy with limited options for treatment and a 5-year survival rate of 11%in the United *** for other types of tumors,such as colorectal cancer,aberrant de novo lipid synthesis and reprogrammed lipid metabolism have been suggested to be associated with PDAC development and *** To identify the possible involvement of lipid metabolism in PDAC by analyzing in tumoral and non-tumoral tissues the expression level of the most relevant genes involved in the long-chain fatty acid(FA)import into *** A gene expression analysis of FASN,CD36,SLC27A1,SLC27A2,SLC27A3,SLC27A4,SLC27A5,ACSL1,and ACSL3 was performed by qRT-PCR in 24 tumoral PDAC tissues and 11 samples from non-tumoral pancreatic tissues obtained via fine needle aspiration or via surgical *** genes were considered significantly dysregulated between the groups when the p value was<0.05 and the fold change(FC)was≤0.5 and≥*** We found that three FA transporters and two long-chain acyl-CoA synthetases genes were significantly upregulated in the PDAC tissue compared to the non-tumoral tissue:SLC27A2(FC=5.66;P=0.033),SLC27A3(FC=2.68;P=0.040),SLC27A4(FC=3.13;P=0.033),ACSL1(FC=4.10;P<0.001),and ACSL3(FC=2.67;P=0.012).We further investigated any possible association between the levels of the analyzed mRNAs and the specific characteristics of the tumors,including the anatomic location,the lymph node involvement,and the presence of metastasis.A significant difference in the expression of SLC27A3(FC=3.28;P=0.040)was found comparing patients with and without lymph nodes involvement with an overexpression of this transcript in 17 patients presenting tumoral cells in the lymph *** Despite the low number of patients analyzed,these preliminary results seem to be *** lipid metabolism through a broad strategy could be a beneficial way to treat this *** in vitro and in vivo s

关键词： Carcinoma Pancreatic ductal Fatty acid transport Gene expression Biomarkers

Diabetes mellitus and glymphatic dysfunction:Roles for oxidative stress,mitochondria,circadian rhythm,artificial intelligence,and imaging

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World Journal of Diabetes 2025年第1期16卷 39-48页

作者： Kenneth Maiese national Heart Lungand Blood InstituteNational Institutes of HealthBethesdaMD 20810United States

Diabetes mellitus(DM)is a debilitating disorder that impacts all systems of the body and has been increasing in prevalence throughout the *** represents a significant clinical challenge to care for individuals and prevent the onset of chronic disability and ultimately *** cellular mechanisms for the onset and development of DM are multi-factorial in origin and involve pathways associated with the production of reactive oxygen species and the generation of oxidative stress as well as the dysfunction of mitochondrial cellular organelles,programmed cell death,and circadian rhythm *** pathways can ultimately involve failure in the glymphatic pathway of the brain that is linked to circadian rhythms disorders during the loss of metabolic *** studies incorporate a number of promising techniques to examine patients with metabolic disorders that can include machine learning and artificial intelligence pathways to potentially predict the onset of metabolic dysfunction.

关键词： Artificial intelligence Circadian rhythm Clock genes Diabetes mellitus magnetic resonance imaging Glymphatic pathway Mitochondria Oxidative stress Programmed cell death Sleep fragmentation

Secondary Calcification of Planktic Foraminifera from the Indian Sector of Southern Ocean

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Acta Geologica Sinica(English Edition) 2015年第1期89卷 27-37页

作者： Rahul MOHAN Suhas S.SHETYE Manish TIWARI Narayanpillai ANILKUMAR national Centre for Antarctic and Ocean Research national institute of oceanography

This study focused on planktic foraminifera in plankton tows and surface sediments from the western Indian sector of Southern Ocean in order to evaluate the potential foraminiferal secondary calcification and/or dissolution in the sediment. It is found that the symbiotic foraminiferal species are abundant in the subtropical region, whereas non-symbiotic species dominate in the sub-Antarctic and polar frontal regions. The distribution of the symbiotic and non-symbiotic foraminiferal species is controlled by temperature, salinity, light, nutrients and phytoplankton biomass. There is also a lateral southern extent in abundance of planktic foraminifera from surface sediments to plankton tows. The shell weights of the planktic foraminifera N. pachyderma, G. bulloides and G. ruber within the surface sediments are on an average heavier by 27%, 34% and 40% respectively than shells of the same size within the plankton tows, indicative of secondary calcification. The planktic foraminiferal isotopes show the presence of heavier isotopes in the surface sediment foraminifera as compared to plankton tows, thus confirming secondary calcification. Secondary calcification in G. ruber occurs in the euphotic zone, whereas in case of N. pachyderma and G. builoides it is at deeper depths. We also observed a decrease in the shell spines in surface sediment foraminifera as compared to plankton tows, indicative of the morphological changes that foraminifera underwent during gametogenesis.

关键词： Southern Ocean foraminifera climate change stable isotopes shell weight