Cyclic Variation of Residual (CO2 + H2O) and Total Pressure in Conifer Stem and Woody Root Tree Rings

Tree-ring chronologies of stem discs and core samples have been widely used to reconstruct the climatic conditions of tree growth. However, insufficient attention has been given to the fact that root and stem wood accumulate biogenic gases, whose distribution in annual rings can also be related to the climate-dependent features of tree growth. The study of chronologies of gas samples extracted under vacuum from the wood of tree-ring discs of the Siberian stone pine (Pinus sibirica Du Tour), Scots pine (Pinus sylvestris L.), Siberian larch (Larix sibirica Ledeb.) and Siberian spruce (Picea obovata Ledeb.) suggests that annual distributions of CO2 and H2O in the rings and pressure variation in extracted samples follow a cyclic pattern. It was found that the sample pressure and the content of CO2 and H2O in the annual rings in stems and roots of the Siberian stone pine and Scots pine from Tomsk (Russia) area are characterized by varied time cycles, including periods of about 4 and 11 years, the latter corresponding to the period of the solar activity cycle. The four-year cycle in the above chronologies is explained by the presence of similar cycles in temperature and precipitation chronologies, where cyclic variations of CO2 in the rings can be interpreted as a response of the plant to the change in the climatic conditions. The established cyclic variation of the pressure and CO2 content in tree rings in stems and roots indicates that CO2 release into the atmosphere should also follow a cyclic pattern. Therefore, to estimate correctly the release of CO2 by tree stems and large roots, long-term measurements are require

Циклические вариации остаточного (СО2 + Н2О) и полного давления в древесине колец ствола и корня хвойных деревьев

Tree-ring chronologies of stem discs and core samples have been widely used to reconstruct the climatic conditions of tree growth. However, insufficient attention has been given to the fact that root and stem wood accumulate biogenic gases, whose distribution in annual rings can also be related to the climate-dependent features of tree growth. The study of chronologies of gas samples extracted under vacuum from the wood of tree-ring discs of the Siberian stone pine (Pinus sibirica Du Tour), Scots pine (Pinus sylvestris L.), Siberian larch (Larix sibirica Ledeb.) and Siberian spruce (Picea obovata Ledeb.) suggests that annual distributions of CO2 and H2O in the rings and pressure variation in extracted samples follow a cyclic pattern. It was found that the sample pressure and the content of CO2 and H2O in the annual rings in stems and roots of the Siberian stone pine and Scots pine from Tomsk (Russia) area are characterized by varied time cycles, including periods of about 4 and 11 years, the latter corresponding to the period of the solar activity cycle. The four-year cycle in the above chronologies is explained by the presence of similar cycles in temperature and precipitation chronologies, where cyclic variations of CO2 in the rings can be interpreted as a response of the plant to the change in the climatic conditions. The established cyclic variation of the pressure and CO2 content in tree rings in stems and roots indicates that CO2 release into the atmosphere should also follow a cyclic pattern. Therefore, to estimate correctly the release of CO2 by tree stems and large roots, long-term measurements are requiredДревесно-кольцевые хронологии спилов и кернов деревьев широко используются для реконструкций климатических условий роста дерева. Однако остается в стороне тот факт, что древесина корней и стволов сохраняет внутри себя биогенные газы, распределение которых по годичным кольцам также может отражать климатические особенности роста дерева. Исследование хронологий газовых проб, извлекаемых под вакуумом из древесины годичных колец спилов кедра (Pinus sibirica Du Tour), сосны (Pinus sylvestris L.), лиственницы (Larix sibirica Ledeb.), ели (Picea obovata Ledeb), указывает на то, что погодичные распределения сохранившихся в кольцах СО2, Н2О и вариации давления извлекаемой пробы носят циклический характер. Обнаружено, что давление пробы, содержание СО2 и Н2О в годичных кольцах стволов и корней кедра и сосны из района Томска (Россия) испытывают вариации различных временных масштабов, в том числе вариации с периодами около 4 и 11 лет, последний соответствует периоду цикла солнечной активности. Появление цикла с периодом 4 года в найденных хронологиях объясняется существованием подобных циклов в хронологиях температур и осадков, а циклические вариации регистрируемого в кольцах СО2 можно считать реакцией растения на изменение климатических условий. Из обнаруженной циклической вариации давления и СО2 в кольцах спилов стволов и корней деревьев следует, что выделение в атмосферу СО2 должно носить также циклический характер, поэтому для корректной оценки выделения СО2 стволами и крупными корнями следует проводить длительные измерени

Циклические вариации остаточного (СО2 + Н2О) и полного давления в древесине колец ствола и корня хвойных деревьев

Tree-ring chronologies of stem discs and core samples have been widely used to reconstruct the climatic conditions of tree growth. However, insufficient attention has been given to the fact that root and stem wood accumulate biogenic gases, whose distribution in annual rings can also be related to the climate-dependent features of tree growth. The study of chronologies of gas samples extracted under vacuum from the wood of tree-ring discs of the Siberian stone pine (Pinus sibirica Du Tour), Scots pine (Pinus sylvestris L.), Siberian larch (Larix sibirica Ledeb.) and Siberian spruce (Picea obovata Ledeb.) suggests that annual distributions of CO2 and H2O in the rings and pressure variation in extracted samples follow a cyclic pattern. It was found that the sample pressure and the content of CO2 and H2O in the annual rings in stems and roots of the Siberian stone pine and Scots pine from Tomsk (Russia) area are characterized by varied time cycles, including periods of about 4 and 11 years, the latter corresponding to the period of the solar activity cycle. The four-year cycle in the above chronologies is explained by the presence of similar cycles in temperature and precipitation chronologies, where cyclic variations of CO2 in the rings can be interpreted as a response of the plant to the change in the climatic conditions. The established cyclic variation of the pressure and CO2 content in tree rings in stems and roots indicates that CO2 release into the atmosphere should also follow a cyclic pattern. Therefore, to estimate correctly the release of CO2 by tree stems and large roots, long-term measurements are requiredДревесно-кольцевые хронологии спилов и кернов деревьев широко используются для реконструкций климатических условий роста дерева. Однако остается в стороне тот факт, что древесина корней и стволов сохраняет внутри себя биогенные газы, распределение которых по годичным кольцам также может отражать климатические особенности роста дерева. Исследование хронологий газовых проб, извлекаемых под вакуумом из древесины годичных колец спилов кедра (Pinus sibirica Du Tour), сосны (Pinus sylvestris L.), лиственницы (Larix sibirica Ledeb.), ели (Picea obovata Ledeb), указывает на то, что погодичные распределения сохранившихся в кольцах СО2, Н2О и вариации давления извлекаемой пробы носят циклический характер. Обнаружено, что давление пробы, содержание СО2 и Н2О в годичных кольцах стволов и корней кедра и сосны из района Томска (Россия) испытывают вариации различных временных масштабов, в том числе вариации с периодами около 4 и 11 лет, последний соответствует периоду цикла солнечной активности. Появление цикла с периодом 4 года в найденных хронологиях объясняется существованием подобных циклов в хронологиях температур и осадков, а циклические вариации регистрируемого в кольцах СО2 можно считать реакцией растения на изменение климатических условий. Из обнаруженной циклической вариации давления и СО2 в кольцах спилов стволов и корней деревьев следует, что выделение в атмосферу СО2 должно носить также циклический характер, поэтому для корректной оценки выделения СО2 стволами и крупными корнями следует проводить длительные измерени

TMC125 exerts similar initial antiviral potency as a five-drug, triple class antiretroviral regimen

Objective: TMC125, a next generation, non-nucleoside reverse transcriptase inhibitor (NNRTI), demonstrated a remarkable decline of plasma HIV-1 RNA during a phase IIa study. We compared the initial rate of decline of plasma HIV-1 RNA achieved by TMC125 monotherapy with that of a triple class, five-drug regimen, containing drugs from all three currently licensed classes (zidovudine, lamivudine, abacavir, indinavir and nevirapine). Methods: The decline in plasma HIV-1 RNA of 12 HIV-1 infected, antiretroviral (ART) naive patients treated for 1 week with TMC125 monotherapy was compared with that observed in the ERA study (n = 11). The plasma HIV-1 RNA elimination rate constant was calculated based on at least four plasma HIV-1 RNA measurements during the first week of treatment (first-order elimination) and compared using the Student's t test. Results: Median ages were 23 and 38 years for TMC125 and ERA patients, respectively (P = 0.001), median baseline plasma HIV-1 RNA levels were 4.2 and 4.8 log10 copies/ml (P = 0.001) and median baseline CD4 T-cell counts were 458 × 106 and 360 × 106 cells/l (P = 0.08). The median plasma HIV-1 RNA elimination rate constant was 0.68/day in TMC125 treated patients, and 0.56/day in ERA participants (P = 0.24). The median decline in plasma HIV-1 RNA after 7 days was 1.92 and 1.76 log 10 copies (P = 0.77) and the median increase of CD4 T cells was 119 × 106 and 60 × 106 cells/l, respectively (P = 0.29). Conclusion: Monotherapy with TMC125 in ART-naive, HIV-1-infected individuals resulted in a similar rate of decline of plasma HIV-1 RNA during 1 week of therapy as therapy with a five-drug regimen

TMC125 exerts similar initial antiviral potency as a five-drug, triple class antiretroviral regimen

Objective: TMC125, a next generation, non-nucleoside reverse transcriptase inhibitor (NNRTI), demonstrated a remarkable decline of plasma HIV-1 RNA during a phase IIa study. We compared the initial rate of decline of plasma HIV-1 RNA achieved by TMC125 monotherapy with that of a triple class, five-drug regimen, containing drugs from all three currently licensed classes (zidovudine, lamivudine, abacavir, indinavir and nevirapine). Methods: The decline in plasma HIV-1 RNA of 12 HIV-1 infected, antiretroviral (ART) naive patients treated for 1 week with TMC125 monotherapy was compared with that observed in the ERA study (n = 11). The plasma HIV-1 RNA elimination rate constant was calculated based on at least four plasma HIV-1 RNA measurements during the first week of treatment (first-order elimination) and compared using the Student's t test. Results: Median ages were 23 and 38 years for TMC125 and ERA patients, respectively (P = 0.001), median baseline plasma HIV-1 RNA levels were 4.2 and 4.8 log(10) copies/ml (P = 0.001) and median baseline CD4 T-cell counts were 458 X 10(6) and 360 X 10(6) cells/l (P = 0.08). The median plasma HIV-1 RNA elimination rate constant was 0.68/day in TMC125 treated patients, and 0.56/day in ERA participants (P = 0.24). The median decline in plasma HIV-1 RNA after 7 days was 1.92 and 1.76 log(10) copies (P = 0.77) and the median increase of CD4 T cells was 119 X 10(6) and 60 X 106 cells/l, respectively (P = 0.29). Conclusion: Monotherapy with TMC125 in ART-naive, HIV-1-infected individuals resulted in a similar rate of decline of plasma HIV-1 RNA during 1 week of therapy as therapy with a five-drug regimen. (C) 2003 Lippincott Williams Wilkin

Occurrences of Threatened Species included in the Third Edition of the Red Data Book of the Komi Republic (Russia)

The purpose of the data paper was to introduce into scientific literature the results of scientific work carried out for the third edition of the 'Red Data Book of the Komi Republic'. The article reflects methodological approaches to the formation of a list of rare and in need of protection species and describes the corresponding datasets published in GBIF.Information about 7,187 occurrences of 438 rare species and infraspecies included in the third edition of the 'Red Data Book of the Komi Republic' have been published