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Although many studies have attempted to reconstruct millennial‐scale hurricane patterns using various proxy‐based methods, it is still unclear what the most effective proxies are to identify storm surge deposits in different environmental settings. This study quantitatively compares the application of grain‐size, loss‐on‐ignition, stable isotopes, X‐ray fluorescence, and palynological proxies in paleotempestology from an organic‐rich environment in the Florida Everglades. The nonparametric tests indicate that only 9 among the 27 parameters (mean diameter, %water, %organic, %carbonate, Ca, Sr, Ca/Ti, Cl/Br, and marine microfossils) exhibited significant differences between storm‐surge and in situ deposits. The principal component analysis shows that five marine indicators (Sr, Ca, Ca/Ti, %Carbonate, and Marine microfossils) have the closest association with the allochthonous samples, while Cl/Br and Mz are the most sensitive proxies in low‐ and high‐energy environments, respectively. Moreover, organic geochemical proxies (e.g., δ13C and δ15N of bulk sedimentary organic matter) are ineffective for identifying storm‐surge deposits in organic‐rich mangrove environments. Plain Language Summary: To help objectively identify the occurrence of storm‐surge deposits in coastal sediment cores, this study uses a statistical approach to evaluate the effectiveness of 27 widely used sedimentological, organic and inorganic geochemical, and biological parameters in distinguishing allochthonous deposits from autochthonous deposits in an organic‐rich environment in the Florida Everglades. The results show that Ca, Sr, Ca/Ti, and marine microfossil are four of the most sensitive parameters to distinguish storm‐surge deposits in organic‐rich environments in south Florida. In addition, Cl/Br can be used to indicate storm surge inundation in further inland and lower‐energy environments. Moreover, organic geochemical proxies cannot effectively distinguish storm‐surge deposits from in situ deposits in mangrove‐dominated coastal zones. Future studies need to explore the use of more specific organic geochemical proxies (e.g., biomarker) in mangrove‐dominated environments and evaluate the effective proxies in detecting storm deposits from sandy, deltaic/estuarine, and nontropical coastal environments. Key Points: Ca, Sr, Ca/Ti, and marine microfossil are the most sensitive parameters to identify storm‐surge deposits in organic‐rich environmentsCl/Br can be used to indicate storm surge inundation in further inland and lower energy environmentsOrganic geochemical proxies cannot effectively distinguish storm‐surge deposits from in situ deposits in mangrove‐dominated coastal zones [ABSTRACT FROM AUTHOR]

The corrosion of steel fibers is a direct cause of the deterioration of steel fiber-reinforced concrete in chloride environments. This study mainly investigated the corrosion behavior of steel fibers exposed to NaCl solutions with pH=7 , 10, 11, 12, and 13. The corrosion rate of the steel fibers was calculated according to the change of the diameter and ultimate tensile load. The electrochemical parameters of the steel fibers corrosion were continuously monitored. The morphology of the steel fibers affected by chloride attack was observed by scanning electron microscope (SEM). The results reveal that the corrosion rate of the steel fibers decreased as the pH of the NaCl solution increased from 7 to 13, and it was very small at pH≥12. According to the open circuit potential, corrosion potential, corrosion current density, and electrochemical impedance spectroscopy, the steel fibers exhibited a high corrosion tendency and corrosion rate when exposed to NaCl solutions with pH≤12. However, they exhibited low corrosion tendency in the chloride solution with pH=13. The surface roughness of the steel fibers exhibited only a slight increase after exposure to the NaCl solution with pH=13 for 180 days. [ABSTRACT FROM AUTHOR]

Ammonium-based alkali-catalyzed [beta]-elimination under nonreducing conditions was investigated in detail for the stability of the released mucin-type O-glycan chains with [beta]1,3-1inked cores. In contrast to the previously studied [beta]1,4-linkage of the N-glycan-type, which was shown to be stable under the ammonium-based alkaline conditions, the [beta]l,3-linkaga is labile toward alkaline treatment and considerable peeling was observed with both model heptasaccharides and standard glycoproteins. The former include eight reducing glucoheptasaccharides with different and commonly occurring linkages ([alpha]l,2-, [beta]1,2-, [alpha]l,3-,[beta]1,3-, [alpha]l,4-, [beta]1,4-, [alpha]1,6-, and [beta]l,6-linkages), and the latter include mucin-type bovine submaxillary mucin and bovine fetuin, which contains both O-and N-glycans. The results indicated that complete prevention of peeling under nonreducing alkali-catalyzed hydrolysis conditions remains difficult. The yields of released O-and N-glycans were also assessed by use of the two glycoproteins as models. Compared with conventional procedures, Carlson degradation for O-glyean release and PNGase F digestion for N-glycan release, the nonreducing ammonium-based alkaline hydrolysis gave lower yields. Great care has to be taken when employing such nonreducing alkaline conditions in glycomic analysis and in obtaining glycoprotein glycans for functional studies. 10.1021/ac102300r

The Asian interior has the largest mid-latitude arid zone in the Northern Hemisphere, and so has become increasingly attractive for studying the initiation and the past extent of aridification in this zone. Given the enormousness of the Asian interior, it remains unclear how old and extensive the eolian deposits might have been, and what wind regimes have been responsible for the formation of the mid-latitude arid zone. Here we report new eolian records of widespread Tertiary eolian deposits in a region far from the Chinese Loess Plateau, the giant Junggar inland basin of northwestern China. Our results demonstrate that the earliest eolian deposition initiated ca. 24 Ma. We interpret that the Tertiary eolian dust in the Junggar Basin was transported by westerly winds, possibly from areas in Kazakhstan; the dust differs from the airborne dust transported by winter monsoon winds from the deserts of Mongolia and northern China that accumulated on the Loess Plateau. These results further reveal that the climate pattern, similar to that of the present, has prevailed at least since the latest Oligocene in Central Asia. doi: 10.1130/G30776.1

The Tianshan Range is one of the longest and highest mountain belts in Central Asia, stretching east-west for ~2500 km. Uplift of this late Paleozoic orogenic belt resulted from intracontinentai deformation caused by the collision of the Indian and Eurasian plates during the Cenozoic era. To constrain the timing of Cenozoic tectonic deformation of the Tianshan Range, we analyzed the magnetostratigraphy of 3780-m-thick Neogene deposits from the Kuqa foreland basin of southern Tianshan. The geometry measurements and magnetic fabric data show that syntectonic growth strata began to accumulate at ~6.5 Ma ago, indicating that crustal shortening initiated in the latest Miocene. The increase in sedimentation rate and an abrupt change of the magnetic fabric parameters also occurred at 6.5 Ma, accompanied by onset of syntectonic growth strata. The latest Miocene crustal shortening is a significant tectonic event in the foreland basin of the southern Tianshan Range in response to the India-Eurasia collision. doi: 10.1130/G30278A.1

The glycosaminoglycan (GAG) family of biomacromolecules is composed acidic and linear chains of repeating disaccharide units. Quantitative disaccharide composition analysis is essential for the study and characterization of GAGs. Heparan sulfate and heparin consist of multiple disaccharide units and can be well-separated by ion-pairing reversed-phase microflow high-performance liquid chromatography (IPRP-Mf-HPLC). Each disaccharide can be detected and its mass confirmed by electrospray ionization mass spectrometry (ESI-MS). Isotopically enriched disaccharides were prepared chemoenzymatically from a uniformly [sup.13]C,[sup.15]N-labeled N-acetylheparosan (-GlcA(I[right arrow]4)GlcNAc-) obtained from the fermentation of E. coli K5. These isotopically enriched disaccharides have identical HPLC retention times and mass spectra as their unlabeled counterparts and were used in liquid chromatography--mass spectrometry (LC--MS) as internal standards. The ratio of intensifies between each pair of enriched and nonenriched disaccharides showed a linear relationship as a function of concentration. With the use of these calibration curves, the amount of each disaccharide ([greater than or equal to] 2 ng/ disaccharide) could be quantified in four heparan sulfate samples analyzed by this method.