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The human TRPA1 intrinsic cold and heat sensitivity involves separate channel structures beyond the N-ARD domain
TRP channels sense temperatures ranging from noxious cold to noxious heat. Whether specialized TRP thermosensor modules exist and how they control channel pore gating is unknown. We studied purified human TRPA1 (hTRPA1) truncated proteins to gain insight into the temperature gating of hTRPA1. In patch-clamp bilayer recordings, ∆1–688 hTRPA1, without the N-terminal ankyrin repeat domain (N-ARD), was more sensitive to cold and heat, whereas ∆1–854 hTRPA1, also lacking the S1–S4 voltage sensing-like domain (VSLD), gained sensitivity to cold but lost its heat sensitivity. In hTRPA1 intrinsic tryptophan fluorescence studies, cold and heat evoked rearrangement of VSLD and the C-terminus domain distal to the transmembrane pore domain S5–S6 (CTD). In whole-cell electrophysiology experiments, replacement of the CTD located cysteines 1021 and 1025 with alanine modulated hTRPA1 cold responses. It is proposed that hTRPA1 CTD harbors cold and heat sensitive domains allosterically coupled to the S5–S6 pore region and the VSLD, respectively
North Pacific-wide spreading of isotopically heavy nitrogen during the last deglaciation: Evidence from the western Pacific
Sedimentary delta(15) N records in two IMAGES cores (MD012404 and MD012403) retrieved from the Okinawa Trough (OT) in the western North Pacific reveal deglacial increases with two peaks occurring during the Bolling/Allerod and the Preboreal/early Holocene periods. These peaks are synchronous with previously reported delta(15) N peaks in the Eastern Tropical North Pacific, although the amplitudes (from 3.8 to 5.8%) are much smaller in the OT. Similar delta(15) N values for the last glacial maximum and the late-Holocene observed by us at a site far from the present-day zones of water-column denitrification (WCD) indicate that the mean N-15/N-14 of nitrate in the upper ocean did not differ much between the two climate states. The accumulation rate of organic carbon and total sulfur content are used as indices of the local WCD potential. The results suggest that enhancement of global WCD rather than local denitrification should be responsible for the deglacial maxima of sedimentary delta(15) N in the Okinawa Trough. Our data could provide additional constraints to better understand changes in nitrogen budget during the glacial to interglacial transition.National Science Council of Taiwan [NSC 96-2611-M-001-005]; State Key Laboratory of Marine Environmental Science, ; Xiamen University, Xiame
Tropical limestone forest resilience during MIS-2: implications for Pleistocene foraging & modern conservation
In this paper we present a multi-proxy study of tropical limestone forest and its utilization by human groups during the major climatic and environmental upheavals of MIS-2 (29-11.7 ka BP). Our data are drawn from new field research within the Tràng An World Heritage property, on the edge of the Red River Delta, northern Vietnam. Key findings from this study include 1) that limestone forest formations were resilient to the large-scale landscape transformation and inundation of the Sunda continent at the end of the last glaciation; 2) that prehistoric human groups were probably present in this habitat through-out MIS-2; and 3) that the forested, almost insular, karst of Tràng An provided foragers with a stable resource-base in a wider changing landscape. These results have implications for our understanding of the prehistoric utilization of karst environments and resonance for conservation efforts in the face of climate and environmental change today
Wpływ jonów ołowiu oraz kadmu na parametry bilansu wodnego i zawartość barwników fotosyntetycznych u spartiny preriowej (Spartina pectinata Bosk ex Link.)
Theoretical distributions in approximation of breast height diameter structure in upper mountain zone Norway spruce stands in 'Snieżnik Klodzki' nature reserve
The study on the structure of Norway spruce old−growth stands of original provenience in upper mountain zone was carried out in a nature reserve ‘Śnieżnik Kłodzki', located in the Lądek Zdrój Forest District (SW Poland). The fieldwork was conducted in three spruce stands located at the altitude of 1,215 and 1,235 m a.s.l. The breast height diameters (dbh) of living trees were characterized. The aim of this study is to characterize the structure of dbh of trees in spruce stands of subalpine forest. Implementation of the objective will be associated with the characteristics of empirical distributions dbh and an indication of theoretical distributions of continuous random variable best approximating the structure of dbh. The comparison of empirical dbh distributions with 36 theoretical distributions were carried out, but goodness−of−fit tests proven statistically significant compatibility with seventeen of them: beta (4−parameter), Cauchy, exponential power, folded normal, gamma (3−parameter), generalized logistic, Laplace, logistic, loglogistic, loglogistic (3−parameter), lognormal (3−parameter), noncentral chi−square, normal, smallest extreme value, triangular, Weibull and Weibull (3−parameter). The dbh distributions in upper mountain spruce stands are the best fitted with logistic distribution, and subsequently loglogistic (3−parameter), generalized logistic and Weibull (3−parameter) distributions. That four distributions can be used in individual tree growth models while generating structure dbh of trees in the stand. The knowledge of dbh structure in protected stands could be helpful in shaping spruce stand structure in planned silvicultural treatments, and shows the need for silvicultural treatments in upper mountain spruce stands
A two-level morphology of Malagasy
We present a two-level model of Malagasy nominal and verbal morphology (Beesley and Karttunen, 2003), based primarily on the discussion of Malagasy morphology in Keenan and Polinsky (1998) and Randriamasimanana (1986). Words in Malagasy are built from roots by means of a variety of morphological operations such as affixation and reduplication. The present paper analyzes productive patterns of nominal and verbal morphology, describing genitive compounding and suffixation for nouns, and various derivational processes involving compounding and affixation for verbs
B (2008) Investigation of electromagnetic wave absorber based on carbon fiber reinforced aerated concrete using time-domain method
The electromagnetic wave absorbers prepared from autoclaved aerated concrete containing carbon fibers as additions in the shape of slabs with pyramids cut on one plane of these slabs were tested using dc microwave source and the time-domain method. It was demonstrated that autoclaved aerated concrete allows one to fabricate electromagnetic wave absorbers which have a reflection coefficient up to -30 dB in the frequency range from 2 GHz to 18 GHz
ECOLOGICAL STUDY ON PROTOZOA IN THE SEDIMENT OF THE THREE-GORGES AREA OF THE CHANGJIANG RIVER CHINA
This paper reports on the study on the protozoan community structure of the immersed sediment in the Three-Gorges Area of the Changjiang River. Protozoa observed included 7 phytoflagellates, 12 zooflagellates, 49 amoebae and 16 ciliates. Sarcodina dominated in sediment, ciliates in water. Analysis of species and horizontal density distribution of protozoan in sediment in 28 sampling points reflected the pollution degree of water quality at every site. It was shown that heavy metal contamination in sediment has some effects on the distribution of protozoan species in the Changjian River
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