Environmental magnetism of Kucukcekmece Lagoon sediments (Istanbul): paleoclimate records for the last 3800 years in northwest Anatolia

NASA Astrophysics Data System (ADS)

Makaroglu, O.; Nowaczyk, N. R.; Cagatay, M. N.; Acar, D.; Akcer On, S.; Orbay, N.

2016-12-01

We present the results of high resolution mineral magnetic and geochemical analyses from the 512 cm long Core KCL12P2, recovered from the deepest basin of Küçükçekmece Lagoon (40.98° N, 28.76° E), located north of the Sea of Marmara. According to the age-depth model based on radiocarbon, paleomagnetic and global proxy correlation, the core sedimentary section covers the last 3800 years and consists of three different lithologies, based on lithological variations and down core mineral magnetic composition. Lithology A is composed of grey to brown laminated sediment that is siderite-rich as evidenced by the thermomagnetic analysis. It has low to intermediate Ca and Sr, low Ca/Ti and high Br (organic carbon). This lithology was deposited during relatively humid periods with high organic productivity and high terrigeneous input, which occurred during 3150-1700 a BP, 3600-3350 a and 1500 a BP-present. Lithology B consists of homogeneous black sediments characterized by the predominance of single magnetic domain (SD) and the highest magnetic susceptibility (100-2200x10-6), S-ratios (0.95 - 0.99), HIRM (100-2400) and SIRM/κLF (58-100kAm-1) values producing distinct peaks. The thickness of this lithology varies in thickness between 5 and 10 cm in the core. The thermomagnetic and mineral magnetic parameters indicate the predominance of greigite in lithology B, which occurred during 1500, 3200 and 3600 a BP some decadal periods after each seawater intrusion and establishment of high sulphate concentrations in the lagoon following each dry period represented by lithology C in the sequence. Lithology C is a homogeneous grey mud with low S-ratio, high κLF and high HIRM values indicating an increase in the content of high coercivity magnetic minerals. It is also characterized by high Ca, Sr and Ca/Ti and low Br (low organic carbon). The magnetic and geochemical composition of lithology C indicate that it was deposited during dry periods with low fresh water, nutrient and

Distribution of haptoglobins in different dialect groups of Chinese, Malays and Indians in Singapore.

PubMed

Saha, N; Ong, Y W

1984-07-01

A total of 870 subjects comprising 524 Chinese (from different dialect groups), 231 Malays and 115 Tamil Indians were investigated for the distribution of haptoglobin types and ABO blood groups. Haptoglobins were typed by PAG electrophoresis using discontinuous buffer system. The frequencies of Hp,1 Hp2 and Hp0 were found to be 0.330, 0.670 and 0.029 in Chinese; 0.298, 0.702 and 0.004 in Malays; and 0.167, 0.833 and 0.009 in Indians. The Hainanese had the highest frequency of Hp1 (0.375) followed by Cantonese (0.348), Teochew (0.333) and Hakkas (0.288). The distribution of all the phenotypes of haptoglobin was at equilibrium in all the population groups studied. No association of ABO blood groups was detected with the haptoglobin types. However, there was an excess of AB blood group in persons carrying Hp2 compared with those with Hp1.

Localising People's Theatre in East Asia: Performing Hakka Women and Pear-Growers on Taiwan's Fault Line

ERIC Educational Resources Information Center

Liang, Peilin

2012-01-01

Since the 1960s and 1970s, theatre artists from around the globe initiated a wave of theatre practice that is commonly known today as People's Theatre or Theatre for Empowerment. Transforming its participants from being mere "spectactors" to "spect-actors" capable of articulating their concerns on-stage, the ultimate goal of…

Performance evaluation of elemental analysis/isotope ratio mass spectrometry methods for the determination of the D/H ratio in tetramethylurea and other compounds--results of a laboratory inter-comparison.

PubMed

Bréas, Olivier; Thomas, Freddy; Zeleny, Reinhard; Calderone, Giovanni; Jamin, Eric; Guillou, Claude

2007-01-01

Tetramethylurea (TMU) with a certified D/H ratio is the internal standard for Site-specific Natural Isotope Fractionation measured by Nuclear Magnetic Resonance (SNIF-NMR) analysis of wine ethanol for detection of possible adulterations (Commission Regulation 2676/90). A new batch of a TMU certified reference material (CRM) is currently being prepared. Whereas SNIF-NMR has been employed up to now, Elemental Analysis/Isotope Ratio Mass Spectrometry ((2)H-EA-IRMS) was envisaged as the method of choice for value assignment of the new CRM, as more precise (better repeatable) data might be obtained, resulting in lower uncertainty of the certified value. In order to evaluate the accuracy and intra- and inter-laboratory reproducibility of (2)H-EA-IRMS methods, a laboratory inter-comparison was carried out by analysing TMU and other organic compounds, as well as some waters. The results revealed that experienced laboratories are capable of generating robust and well comparable data, which highlights the emerging potential of IRMS in food authenticity testing. However, a systematic bias between IRMS and SNIF-NMR reference data was observed for TMU; this lack of data consistency rules out the (2)H-IRMS technique for the characterisation measurement of the new TMU CRM.

Red Dawn: Characterizing Iron Oxide Minerals in Atmospheric Dust

NASA Astrophysics Data System (ADS)

Yauk, K.; Ottenfeld, C. F.; Reynolds, R. L.; Goldstein, H.; Cattle, S.; Berquo, T. S.; Moskowitz, B. M.

2012-12-01

indicates the presence of nanogoethite and small particle sizes (< 30 nm). Magnetization experiments indicates that some of the nanogoethite has remanence blocking temperatures above 300 K (and hence larger particle sizes) but it must be a small fraction of the total grain distribution considering that goethite was not indicated at 300 K with Mössbauer. Likewise, Mössbauer spectra indicate that the hematite component is still above the Morin transition (TM=265 K) and in its canted antiferromagnetic state even at 4.2 K. Suppression of the Morin transition in hematite can occur due to reduced crystallinity, cation substitution (e.g., Ti4+, Al 3+), or small particle effects (d< 100 nm). Finally, we compared reflectance with a magnetic parameter (hard isothermal remanent magnetization, HIRM) for ferric oxide abundance to assess the degree to which ferric oxide in these samples might absorb solar radiation. In samples for which both parameters were obtained, HIRM and average reflectance over the visible wavelengths are correlated as a group (r2=0.24). These results indicate that the ferric oxide minerals in Red Dawn dust absorb solar radiation. Much of this ferric oxide occurs likely as grain coatings of nanohematite and nanogoethite, thereby providing high surface area to enhance absorption of solar radiation.

Diversity of lactic acid bacteria in suan-tsai and fu-tsai, traditional fermented mustard products of Taiwan.

PubMed

Chao, Shiou-Huei; Wu, Ruei-Jie; Watanabe, Koichi; Tsai, Ying-Chieh

2009-11-15

Fu-tsai and suan-tsai are spontaneously fermented mustard products traditionally prepared by the Hakka tribe of Taiwan. We chose 5 different processing stages of these products for analysis of the microbial community of lactic acid bacteria (LAB) by 16S rRNA gene sequencing. From 500 LAB isolates we identified 119 representative strains belonging to 5 genera and 18 species, including Enterococcus (1 species), Lactobacillus (11 species), Leuconostoc (3 species), Pediococcus (1 species), and Weissella (2 species). The LAB composition of mustard fermented for 3 days, known as the Mu sample, was the most diverse, with 11 different LAB species being isolated. We used sequence analysis of the 16S rRNA gene to identify the LAB strains and analysis of the dnaA, pheS, and rpoA genes to identify 13 LAB strains for which identification by 16S rRNA gene sequences was not possible. These 13 strains were found to belong to 5 validated known species: Lactobacillus farciminis, Leuconostoc mesenteroides, Leuconostoc pseudomesenteroides, Weissella cibaria, and Weissella paramesenteroides, and 5 possibly novel Lactobacillus species. These results revealed that there is a high level of diversity in LAB at the different stages of fermentation in the production of suan-tsai and fu-tsai.

Magnetic analyses of soils from the Wind River Range, Wyoming, constrain rates and pathways of magnetic enhancement for soils from semiarid climates

NASA Astrophysics Data System (ADS)

Quinton, Emily E.; Dahms, Dennis E.; Geiss, Christoph E.

2011-07-01

In order to constrain the rate of magnetic enhancement in soils, we investigated modern soils from five fluvial terraces in the eastern Wind River Range, Wyoming. Profiles up to 1.2 m deep were sampled in 5-cm intervals from hand-dug pits or natural riverbank exposures. Soils formed in fluvial terraces correlated to the Sacajawea Ridge (730-610 ka BP), Bull Lake (130-100 ka BP) and Pinedale-age (˜20 ka BP) glacial advances. One soil profile formed in Holocene-age sediment. Abundance, mineralogy, and grain size of magnetic minerals were estimated through magnetic measurements. Magnetic enhancement of the A-horizon as well as an increase in fine-grained magnetic minerals occurred mostly in Bull Lake profiles but was absent from the older profile. Such low rates of magnetic enhancement may limit the temporal resolution of paleosol-based paleoclimate reconstructions in semiarid regions even where high sedimentation rates result in multiple paleosols. A loss of ferrimagnetic and an increase in antiferromagnetic minerals occurred with age. Our findings suggest either the conversion of ferrimagnetic minerals to weakly magnetic hematite with progressing soil age, or the presence of ferrimagnetic minerals as an intermediate product of pedogenesis. Absolute and relative hematite abundance increase with age, making both useful proxies for soil age and the dating of regional glacial deposits. All coercivity proxies are consistent with each other, which suggests that observed changes in HIRM and S-ratio are representative of real changes in hematite abundance rather than shifts in coercivity distributions, even though the modified L-ratio varies widely.

Star & Planet Formation Studies and Opportunities with SOFIA

NASA Technical Reports Server (NTRS)

Smith, Kimberly Ennico

2018-01-01

Star formation, the most fundamental process in the universe, is linked to planet formation and thus to the origin and evolution of life. We have a general outline of how planets and stars form, yet unraveling the details of the physics and chemistry continues to challenge us. The infrared and submillimeter part of the spectrum hold the most promise for studying the beginnings of star formation. The observational landscape recently shaped by Spitzer, Herschel and ALMA, continues to challenge our current theories. SOFIA, the Stratospheric Observatory for Infrared Astronomy, equipped with state-of-the-art infrared instrumentation to a vantage point at 45,000 feet (13.7 kilometers) flight altitude that is above 99.9 percent of the Earth's water vapor, enables observations in the infrared through terahertz frequencies not possible from the ground. SOFIA is a community observatory, about to start its sixth annual observing cycle. My talk will focus on recent results in advancing star and planet formation processes using SOFIA's imaging and polarimetric capabilities, and the upcoming science enabled by the 3rd generation instrument High-Resolution Mid-Infrared Spectrometer (HIRMES) to be commissioned in 2019. I will show how mid-infrared imaging is used to test massive star formation theories, how far-infrared polarimetry on sub-parsec scales is directly testing the role of magnetic fields in molecular clouds, and how velocity-resolved high-resolution spectroscopy will push forward our understanding of proto-planetary disk science. I will also summarize upcoming opportunities with the SOFIA observatory. For the latest news about your flying observatory, see https://sofia.usra.edu/.

Cultural dimensions of risk perceptions: A case study on cross-strait driftage pollution in a coastal area of Taiwan.

PubMed

Chiang, Yi-Chang; Chang, Han-Pi

2018-01-15

Constant exploitations of the ocean render numerous present challenges as the ocean is linked to human development. The study focused on cross-strait driftage pollution that poses a great threat to coastal environment under climate change. Several hundred packs of herbicides drifting across the Taiwan Strait were discovered along the coastline of Guanyin District of Taiwan. We compared risk perceptions of the local ethnic groups, Hakka and Fulao, residing in a coastal area of Taiwan and exposed to the herbicide coastal incident under climate change. It is of concern that society's response to every dimension of global climate change is mediated by culture. The Driver-Pressure-State-Impact-Response (DPSIR) cause-effect framework was applied in semi-structured interviews to explore coastal sensitivity and human adaptability. As a result, we indicated that despite the presence of two ethnic groups in the same place exposed to the incident they presented very different risk perceptions on both environmental degradation (ED) and adaptive capacity (AC) due to cultural values. We argued that the herbicide coastal incident involved people's risk perceptions and subsequently influenced their opinions and attitudes towards environmental problems. We concluded that the ethnic trait contributed to adaptive behaviors during environmental change. Culturally appropriate adaptations appeared to enhance risk perceptions and adaptation actions, suggesting a need for more rigorous cultural adaptation guidelines towards climate resilience when designing adaptation interventions for different ethnic groups. Copyright © 2017 Elsevier Ltd. All rights reserved.

Native-Language Phonological Interference in Early Hakka-Mandarin Bilinguals' Visual Recognition of Chinese Two-Character Compounds: Evidence from the Semantic-Relatedness Decision Task

ERIC Educational Resources Information Center

Wu, Shiyu; Ma, Zheng

2017-01-01

Previous research has indicated that, in viewing a visual word, the activated phonological representation in turn activates its homophone, causing semantic interference. Using this mechanism of phonological mediation, this study investigated native-language phonological interference in visual recognition of Chinese two-character compounds by early…

Stifled Stakeholders and Subdued Participation: Interpreting Local Responses Toward Shimentai Nature Reserve in South China

NASA Astrophysics Data System (ADS)

Jim, C. Y.; Xu, Steve S. W.

2002-09-01

In recent decades, protected-area management in many developing countries has been molded to win the support and participation of local people. Increasingly, research initiatives are undertaken to enhance understanding of the perceptions and attitudes of rural stakeholders. The effectiveness of the expanding protected-area system in China is critically constrained by similar considerations of community mentality. This paper provides an empirical assessment of local responses towards conservation efforts based on a case study of the recently established Shimentai Nature Reserve (SNR) situated in Yingde, Guangdong Province, China. Questionnaire surveys, face-to-face interviews, and group discussions were employed to gauge local residents' knowledge, perceptions, and expectations towards the SNR. The study covered seven villages situated in and around the reserve, grouped into far-zone (floodplain) and near-zone (upland) categories, accommodating Hakka (Han) and minority Yao peoples. Many respondents had inadequate knowledge, understanding, and perceptions of the reserve. Although most respondents welcomed the expected park-related dividends, the most affected near-zone villagers anticipated losses due to restriction on traditional resource-extraction activities in the forest. The local expectations were influenced by place of residence, emigration of rural young, and household affluence. The lack of local participation in management and inadequate dissemination of information posed obstacles to effective conservation. The high expectation of accruing benefits from development projects, including tourism, might be misplaced and might not be realized. The present honeymoon period of positive attitudes could end soon if the hopes remain unfulfilled for too long. The need to win sustained local support and provide alternative means of livelihood is emphasized.

Sedimentary record of sub-glacial outburst floods at Laurentian Fan

NASA Astrophysics Data System (ADS)

Leng, Wei; von Dobeneck, Tilo

2016-04-01

Large-scale glacial meltwater discharge could be widely recognized off the eastern Canadian continental margin. At Laurentian Fan, sub-glacial outburst floods eroded Permian-Carboniferous redbeds at Gulf of St. Lawrence and then delivered the reddish sediments by Laurentian Channel. Sedimentary record from four gravity cores (GeoB18514-2, 18515-1, 18516-2 and 18517-1) at the SW slope of the Grand Banks of Newfoundland revealed the major depositional processes since Heinrich event 2 (ca. 22 ka). In the cores, the upper thick Holocene olive-grey silty mud units overly IRD-rich Heinrich 1 layer, five reddish units are distinguished in the lower part. Reddish units get proportionally thinner along the SW slope at higher and more distal positions; instead, separating olive-grey layers get thicker with height and distance. Reddish and olive grey units have sharp boundaries and no signs of erosion. Mean grain size changes abruptly from coarse in grey layers to fine in reddish layers, terrigenous elements (as Al, K, Ti, Fe) and clays (Al/Si) are highly elevated in reddish layers and low in Heinrich layers, which are instead enriched in detrital continental carbonates. Both Heinrich layers and reddish layers have enhanced magnetic susceptibility, but Heinrich layer have higher ferromagnetic (SIRM) content (mafic rocks), while reddish layers have more hematite (HIRM). These five reddish layers differ from event to event, which seems to reflect different mixing ratios of event-related and background sedimentation. This mixing will allow estimating event-specific sedimentation rates. Using mixing ratio combined with 14C dating data could contribute to estimate the sedimentation rate and duration of outburst floods, which could help to build ice sheet retreat history and find the connection with paleoclimate changes.

Pruritus Treatment in Viewpoints of Traditional Persian Medicine.

PubMed

Jazani, Arezoo Moini; Azgomi, Ramin Nasimi Doost; Shirbeigi, Leila

2016-05-01

Pruritus is an unpleasant feeling that can cause the desire of scratching in a person and can be the symptoms of systemic, infectious, and neurological diseases. Pruritus is the most common clinical manifestation of skin diseases. Pruritus prevalence is 8-38% in the general population. Causes and treatments of pruritus have been described by traditional Persian medicine scientists. The aim of this study was to derive general principles of the proposed treatment to reduce or relieve pruritus. This descriptive study, review traditional medicine books including Al canon fil tibb, Al-Hawi, Makhzan ul-adviyyah, Al-Abniyah an-Haghyegh el-adviyah, Tuhfat ul-Momineen and Exir-e-Azam. The above-mentioned documents were derived and classified by keywords such as pruritus, hakka, jarab and sherry. In traditional Persian medicine, there are different causes for pruritus such as accumulation of vapors or acute humors in subcutaneous tissue or weakness of expulsive (Dafi'a) faculty and its treatment is based on removing the causes. Proper nutrition, bathing, and removing pathogenic humors are involved in the treatment. According to this study, some plants such as Cassia fistula, Purslane, Violets, Fumaria, Barley, Coriander, Rose and Terminalia chebula are anti-itching. Proper nutrition is the most important point in health and treatment of humors production with appropriate quality and quantity. Pruritus can be treated by lifestyle modification and using medicinal plants. It could be concluded that traditional Persian medicine therapies can be effective in the treatment of pruritus with mild side effects. By further investigation and research, we can reach more effective treatment methods in the field of traditional Persian medicine along with other new medical therapies.

The heterogeneous health latent classes of elderly people and their socio-demographic characteristics in Taiwan.

PubMed

Liu, Li-Fan; Tian, Wei-Hua; Yao, Hui-Ping

2014-01-01

The health care needs of elderly people were influenced by their heterogeneity. This study aimed to identify the health latent classes of elderly people by using latent class analysis to deal with heterogeneity and examine their socio-demographic characteristics. Data came from the 2005 National Health Interview Survey (NHIS) in Taiwan. In total, 2449 elderly individuals with available health indicators were examined in latent class analysis (LCA), and 2217 elderly community-dwellings with complete socio-demographic data were analyzed by multinomial logistic regression. Four health latent classes were identified which included 1066 (43.5%) people in the High Comorbidity (HC), 152 (6.2%) in the Functional Impairment (FI), 252 (10.3%) in the Frail (FR), and 979 (40.0%) in the Relatively Healthy (RH) group. Multinomial logistic regressions revealed socio-demographic characteristics among health classes. The variables associated with an increased likelihood of being in the FR group were age, female, and living with families. They were also correlated to ethnicity and educations. Apart from age and gender, the Functional Impairment group was less likely to be ethnicity of Hakka, more likely to live with others than were the RH group. The HC group tended to be younger, with higher educations, and more likely to live in urban area than the Functional Impairment group. The correlations between health classes and socio-demographic factors were discussed. The health status of elderly people includes a variety of health indicators. A person-centered approach is critical to identify the health heterogeneity of elderly people and manage their care needs by targeting differential aging. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Clinical and immunological characteristics in 552 systemic lupus erythematosus patients in a southern province of China.

PubMed

Li, Wen-Gen; Ye, Zhi-Zhong; Yin, Zhi-Hua; Zhang, Ke

2017-01-01

The purpose of this study was to gain a better understanding of systemic lupus erythematosus (SLE) in Hakka populations. We studied the demographic, clinical and laboratory characteristics in a cohort of 552 SLE patients diagnosed at the Rheumatology Department in MeiZhou People's Hospital from January 2008 to December 2012. There were 495 women and 57 men (8.7 : 1) with a mean age of 35.3 years (range 12-78 years). The mean age at disease onset and the mean disease duration were 31.8 ± 14.4 years and 3.3 ± 2.8 years, respectively. The most common clinical manifestations were arthritis (61.6%), followed by malar rash (52.7%), photosensitivity (22.8%), mouth ulcers (17.0%) and discoid lupus (14.7%). The prevalence was 46.7% for nephritis (by biopsy), 18.3% for pleuritis, 15.6% for pericarditis and 4.9% for neuropsychiatric manifestations. The most common hematological manifestations were anemia (63.8%), followed by leucopenia (29.0%) and thrombocytopenia (14.9%). Antinuclear antibodies were detected in 99.8% of patients, followed by anti-double-stranded DNA (81.3%), anti-SSA (Sjögren's syndrome antigen A)/Ro (58.7%), anti-ribonucleoprotein (36.8%), anti-Sm (35.7%), and anti-SSB/La (15.0%). Anti-cardiolipin immunoglobulin G (IgG) and IgM were detected in 18.3% and 14.1% of patients, respectively. Active disease and infections were the two major causes of death. The clinical and immunological characteristics of the SLE patients in our study place our population in the middle of the spectrum between other Asian and Caucasian populations. © 2015 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

Mineral magnetic characteristics of the late Quaternary coastal red sands of Bheemuni, East Coast (India)

NASA Astrophysics Data System (ADS)

Srivastava, Priyeshu; Sangode, S. J.; Parmar, Nikita; Meshram, D. C.; Jadhav, Priyanka; Singhvi, A. K.

2016-11-01

The voluminous red sand deposits of Bheemuni in the east coast of India provide record of coastal land-sea interaction during the late Quaternary climatic and eustatic oscillations. Limited information on the origin and depositional environments of these red sands and their chronology is available. We studied two inland to coast cross profiles from Bheemuni red sand deposits using mineral magnetism, color characteristics and Citrate-bicarbonate-dithionite (CBD) extractable pedogenic iron oxides over 23 horizons along with optically stimulated luminescence (OSL) chronology at 6 horizons. The oldest exposed bed had an optical age of 48.9 ± 1.7 ka. Differential ages between the two parallel sections (SOS = 48.9 ± 1.7 to 12.1 ± 0.3 ka and IMD = 29.3 ± 3.5 ka) suggest laterally shifting fluvial sedimentation. Both the profiles show significant amount of antiferromagnetic oxide (hematite) along with ferrimagnetic (magnetite/maghemite) mineral composition. The granulometric (/domain-) sensitive parameters (χFD, χARM, SIRM/χLF and χARM/χLF) indicate variable concentration of superparamagnetic (SP) and single domain (SD) particles between the two profiles. The higher frequency dependent and pedogenic magnetic susceptibilities (χFD and χpedo) in the younger (IMD) profile suggest enhanced pedogenesis under a warm-wet climate post 29.3 ka and also during Holocene. A combination of hard isothermal remanent magnetization (HIRM) and redness rating (RR) index indicates distinct but variable concentration of a) crystalline and b) poorly crystalline (pigmentary) hematites in both the profiles. We consider that the former (#a) is derived from hinterland red soils and possibly due to post-depositional diagenesis, and the latter (#b) precipitated from the dissolved iron under fluvial regime imparting the unique red coloration to Bheemuni sands. Partial to complete alteration of ferromagnesian minerals due to pedogenesis in hinterlands under warm-wet climate was therefore the

Magnetic properties as tracers for source-to-sink dispersal of sediments: A case study in the Taiwan Strait

NASA Astrophysics Data System (ADS)

Horng, Chorng-Shern; Huh, Chih-An

2011-09-01

Different lithologies between Taiwan and southeastern China lead to diverse mineralogical composition for weathering products derived from the two shores of the Taiwan Strait. Pyrrhotite and magnetite are respectively the dominant magnetic minerals associated with fluvial sediments from western Taiwan and southeastern China. While magnetite commonly co-exists with pyrrhotite in sediments sourced from Taiwan, pyrrhotite has not been found in sediments sourced from mainland China. Associated with such a distinction are vast differences in magnetic properties, including magnetic susceptibility (χ), SIRM, HIRM and the S-ratio, which can be used to study the provenances of sediments in the Taiwan Strait and adjoining marginal seas. Based on any two of these parameters, the magnetic characteristics of much of the Taiwan Strait sediment can be explained using a two-endmember mixing model. Source-to-sink dispersal of sediments in the Taiwan Strait can then be traced from the distribution of these parameters. The results not only corroborate an earlier study based on radionuclides and particle size distribution ( Huh et al., 2011) but reveal more diagnostic details. Besides spatial distribution based on a large number (216) of surface sediments, we also analyzed temporal variation of magnetic properties in six well-dated cores collected at key sites along the sediment source-to-sink pathways. From profiles of these parameters in cores from the middle of the northern Taiwan Strait, it is calculated that sediment supply from Taiwan has increased substantially in the past five decades, which may very well be related to accelerated land use and increased frequency of intense rainfalls in Taiwan during the same period. The approach described in this work may be extended to other source-to-sink systems around the world and through time, especially the mountainous islands fringing the Pacific and Indian Oceans in southeastern Asia. As with Taiwan, these islands have high

Mineral magnetism of atmospheric dust over southwest coast of India: Impact of anthropogenic activities and implications to public health

NASA Astrophysics Data System (ADS)

Warrier, Anish Kumar; Shankar, R.; Manjunatha, B. R.; Harshavardhana, B. G.

2014-03-01

We have used rock magnetic techniques in this study to assess atmospheric pollution at five stations in and around Mangalore city on the southwestern coast of India. Samples of dust were collected from two suburban areas (Thokkottu and Pumpwell located respectively ~ 10 km and 3 km from the city center), the city center itself (Milagres) and industrial/port areas (Panambur and Mangalore Refinery and Petrochemicals Limited (MRPL)). Low-frequency magnetic susceptibility (χlf), frequency-dependent susceptibility (χfd), susceptibility of anhysteretic remanent magnetization (χARM) and isothermal remanent magnetization (IRM 20 to 1000 mT) were determined on 23 dust samples and inter-parametric ratios calculated. Results show that samples from suburban areas (particularly Thokkottu) are characterized by low χlf (< 314.1 × 10- 8 m3 kg- 1) and up to 6% χfd, suggesting low levels of pollution and the presence of pedogenic magnetite possibly derived from soils by wind erosion. However, the average χlf of Milagres, Panambur and MRPL dust samples is high by factors of 9.2, 3.3 and 2.6 compared to that of the Thokkottu sample. The Milagres sample contains magnetically "soft" minerals like magnetite, possibly indicating its derivation from motor vehicle exhaust. In contrast, the Panambur dust sample is characterized by magnetically "hard" minerals such as hematite and goethite as it has an 8-fold higher HIRM value compared to the Thokkottu sample. This magnetic signature is perhaps the result of dust particles derived from the grinding of hematite-rich iron ore by the Kudremukh Iron Ore Company Limited (KIOCL) at Panambur and its storage and export through the nearby New Mangalore Port. However, the dust sample from MRPL has magnetically "soft" minerals like magnetite. This magnetic mineral may have originated from petroleum refining processes at MRPL. Particulate pollution from industrial activities and motor vehicle exhaust is a threat to human health and is known to

Paleomagnetic Study of Marine Sediment Core OR715-21 from Eastern Offshore of Taiwan

NASA Astrophysics Data System (ADS)

Lee, T.; Wei, K.; Huh, C.

2009-12-01

This study presents paleomagnetic secular variation results of a marine sediment core, named as OR715-21, taken from eastern offshore of Taiwan (121.5°E, 22.7°N, water depth 760 m). The total recovered length is 1.87 meters. Sediments in the core mainly consist of gray clay and silt. Planktonic foraminiferal shells (>250 μm, >6 mg, Globigerinoides spp. and Orbulina universa) were picked from six levels of the core and subjected to AMS 14C dating for constructing the age model. The results indicated that this core could support the information for the last 7000 years. The averaged sedimentation rate is estimated to be of about 26.5 cm/kyr. Psuedo-single domain (PSD) magnetite is identified as the most important magnetic carrier. Alternating field (AF) demagnetization was applied to treat the u-channel samples of the core. The median destructive field of the samples distributed between 15~25 mT. The characteristic remanent magnetization could be resolved after 20 mT cleaning. The paleo-declinations of the samples varied about ±200 around their mean and their paleo-inclinations varied between 300 and 500 . The variation pattern of the paleo-declination is somehow similar to the pattern compiled by Hyoto et al. (1993) based on the lake and marine sediment records from Japan except the varied amplitude is less between 4000 and 5000 yrB.P. Using NRM/ARM after 20 mT cleaning to simulate the paleo-intensity secular variation, our record shows that an increased trend began from 6500 yrB.P. to 3000 yrB.P., but decreased after. Magnetic proxies of this core indicate that 4 stages of environmental changes has happened in the area studied: (1) high magnetite abundance with relative low oxidized magnetic mineral contents occurred during ~6900 to 6200 yrB.P.; (2) a relative low abundance of magnetite with relative high oxidized magnetic minerals during ~6200 to ~5400 yrB.P.; (3) an abnormal low HIRM with relative higher ARM/SIRM could be found during the time period of ~5400

Rock Magnetic Study in the Methanogenesis Zone, Site U1437, IODP Exp 350, Izu Rear Arc

NASA Astrophysics Data System (ADS)

Kars, M. A. C.; Musgrave, R. J.; Kodama, K.; Jonas, A. S.

2015-12-01

In 2014, IODP Expedition 350 drilled a 1806.5 m deep hole at Site U1437 in the Izu Bonin rear arc. The Site presents an unusual deep methanogenesis zone because of a release of sulfate below the sulfate reduction zone (27-83 mbsf) which may buffer methanogenesis by anaerobic methanogens. Methane abundance gradually increases with depth, with significant abundance at ~750-1459 mbsf with a maximum value at 920 mbsf. The rock magnetic study carried out in Hole U1437D from ~775 to ~1000 mbsf shows a drastic change of the magnetic properties at ~850 mbsf coincidently with a stronger release of methane from < 60 ppm at 841 mbsf to ~300 ppm at 854 mbsf. That also corresponds to a depth interval where no core was recovered (~846-854 mbsf). For the sake of clarity, we call hereafter zone A the depth interval above this non-recovered interval (775-846 mbsf) and zone B the interval below (854-1000 mbsf). Both belong to the same lithostratigraphic unit composed of tuffaceous mudstones intercalated with volcanoclastics. In the zone A, NRM, magnetic susceptibility, ARM, SIRM, HIRM display high values. In the zone B, these parameters show much lower values of one order of magnitude less, except for the interval 936-950 mbsf that corresponds to a local maximum (but still lower values than the zone A). Besides, the rock magnetic parameters for grain size and coercivity, such as ARM/χ, S-ratio and Bcr do not show any variations throughout the entire studied interval, although S-ratio displays slightly lower values from ~850 to ~930 mbsf. Grains are low coercivity pseudo-single domain sized. According to the present data, two preliminary hypotheses can be proposed to explain the observations. 1) The non-recovered interval between the zones A and B can be caused by the presence of a sedimentary hiatus and/or a fault, which may be consistent with the observed change in sedimentation rate. 2) No hiatus in the sedimentation. The changes in the magnetic properties can be explained by a

Preliminary magnetostratigraphy and environmental magnetism of the Lower Cretaceous from the Italian Dolomites

NASA Astrophysics Data System (ADS)

Savian, J. F.; Jovane, L.; Florindo, F.; Lukeneder, A.

2011-12-01

magnetization (HIRM=[IRM900+BIRM300]/2), both were used to investigate the magnetic coercivity of the magnetic carriers. The integrated records indicate that the magnetic mineral assemblage is dominated by low-coercivity minerals, probably magnetite and/or low-titanium titanomagnetite for the upper part of the section. There is a mixture of low and high-coercivity materials in the lower part of the section sections, probably magnetite and hematite. The new magnetostratigraphy allows to constrain the age of the sediments and the environmental magnetism provide information that will be helpful to understand the sedimentation processes.

Composition of dust deposited to snow cover in the Wasatch Range (Utah, USA): Controls on radiative properties of snow cover and comparison to some dust-source sediments

USGS Publications Warehouse

Reynolds, Richard L.; Goldstein, Harland L.; Moskowitz, Bruce M.; Bryant, Ann C.; Skiles, S. McKenzie; Kokaly, Raymond F.; Flagg, Cody B.; Yauk, Kimberly; Berquó, Thelma S.; Breit, George N.; Ketterer, Michael; Fernandez, Daniel; Miller, Mark E.; Painter, Thomas H.

2014-01-01

Dust layers deposited to snow cover of the Wasatch Range (northern Utah) in 2009 and 2010 provide rare samples to determine the relations between their compositions and radiative properties. These studies are required to comprehend and model how such dust-on-snow (DOS) layers affect rates of snow melt through changes in the albedo of snow surfaces. We evaluated several constituents as potential contributors to the absorption of solar radiation indicated by values of absolute reflectance determined from bi-conical reflectance spectroscopy. Ferric oxide minerals and carbonaceous matter appear to be the primary influences on lowering snow-cover albedo. Techniques of reflectance and Mössbauer spectroscopy as well as rock magnetism provide information about the types, amounts, and grain sizes of ferric oxide minerals. Relatively high amounts of ferric oxide, indicated by hard isothermal remanent magnetization (HIRM), are associated with relatively low average reflectance (<0.25) across the visible wavelengths of the electromagnetic spectrum. Mössbauer spectroscopy indicates roughly equal amounts of hematite and goethite, representing about 35% of the total Fe-bearing phases. Nevertheless, goethite (α-FeOOH) is the dominant ferric oxide found by reflectance spectroscopy and thus appears to be the main iron oxide control on absorption of solar radiation. At least some goethite occurs as nano-phase grain coatings less than about 50 nm thick. Relatively high amounts of organic carbon, indicating as much as about 10% organic matter, are also associated with lower reflectance values. The organic matter, although not fully characterized by type, correlates strongly with metals (e.g., Cu, Pb, As, Cd, Mo, Zn) derived from distal urban and industrial settings, probably including mining and smelting sites. This relation suggests anthropogenic sources for at least some of the carbonaceous matter, such as emissions from transportation and industrial activities. The composition

A preliminary study of international migration of the Chinese people.

PubMed

Zhu, G

1994-01-01

within the border of Jinjiang City, and counties in Putian City, in Longxi City, and in Xiamen Prefecture. Guangdong immigrants came from cities, places in the Pearl River Delta area and the Tan River Valley, counties in Xingmei hakka area, and Hainan Island. 90% of immigrants settled in southeast Asia (Thailand, Indonesia, Malaysia, Singapore, the Philippines, Burma, Vietnam, Kampuchea, and Laos), and 8% came to North America and Latin America. Most were men, young, not well educated, and unemployed.

Chinese culture and demographic trends in Thailand and Malaysia.

PubMed

Barbie, J

1992-01-01

The Chinese nationality contributes to over 5 million of 10% of the total population of Thailand and almost 35% of the total population of Malaysia. The aim of this paper is to summarize the nature and extent of Chinese influence on Thai and Malay culture. Migration of Chinese to southeast Asia dates back 2000 years; on the Malay peninsula, the first arrivals were in 1349. In Malaysia, arrivals began in the 15th century. The reasons were population pressure, floods, and famines. Social and political unrest also accounted for migration between 1855 and 1970. The Chinese in Malaysia are characterized as having a lower population growth rate than Malays and an abnormal sex ratio of 1000:930 in 1957, but severe ratios of 8 men to 1 woman in the 1820s. Islam forbids intermarriages. The Chinese have benefited from improvement in health care and had a low birth rate of 25/1000 in 1980. Migration has traditionally been from south China, and included migrations from Fujian, Hakkas, Guangdong, Chaozhou, and Hainan. The Chinese have maintained their own culture among the Muslim population. In Thailand, migrations occurred during the 13th century, following the collapse of Nan-Chao in 1253, but are first recorded during the Ming dynasty at the end of the 16th century. There are larger numbers of Chinese in Thailand than Malaysia. Chinese assimilated and the current rate of annual growth is estimated at 2%. The sex ratio was 1.4:1 in the late 1940s. 50% of the Chinese live in Bangkok and central Thailand. Older traditions are still maintained in Bangkok. There is the Chaozhou opera on Chinese New Year's Day and marriage is still preferred within one's own dialect. After 1946, the Chinese were not permitted to receive their education in their native language. By the third generation, there is greater assimilation. The minority of minorities in Malaysia were the Baba, who spoke better Malay than other Chinese. In Thailand, the comparable minority is the Yunnan who do not belong

A northwest Atlantic environmental magnetic perspective on the Oligocene - Miocene Transition

NASA Astrophysics Data System (ADS)

van Peer, Tim; Xuan, Chuang; Lippert, Peter; Wilson, Paul; Liebrand, Diederik

2016-04-01

(possibly of biogenic origin) and a coarse-grained non-stoichiometric haematite component as remanence carriers of the sediments. Variations in the magnetic particle concentration, inferred from bulk magnetic susceptibility (χ), qualitatively co-vary with a global stacked oxygen-isotope curve on at least an ~100 kyr scale. The ratios between χ and anhysteretic remanent magnetisation (ARM) and ARM/IRM are typically used to assess bulk magnetite grain size. These ratios, as well as the HIRM ('hard' IRM) component (haematite/goethite) and the L-ratio, decrease approximately by a factor of 2 at the onset of the Mi1 event in Subchron C6Cn.3n. All of these environmental magnetic changes are coincident with an abrupt increase in the Zr/Ti values - a proxy for detrital input, measured by continuous X-Ray Fluorescence core scanning. Collectively, these observations are consistent with shifts in supply or preservation of the non-stoichiometric haematite component throughout the measured section. We tentatively interpret these changes in deep sea magnetic mineralogy to reflect changes in sediment provenance, grain size, or both, which are likely related to changes in DWBC strength and source regions; this hypothesis can be tested by additional magnetic fabric, sediment particle, and geochemical studies. Our work demonstrates that continuous magnetic measurements can reveal important changes in contourite drifts, and hints at how major climatic events such as Mi1 may influence ocean current systems such as the DWBC.