Annual rhythm of germination of seeds of Mesembryanthemum nodiflorum 32 years after collection

2005 ◽  
Vol 15 (3) ◽  
pp. 249-253 ◽  
Author(s):  
Yitzchak Gutterman ◽  
Tanya Gendler

Dry plants of Mesembryanthemum nodiflorum L. (Aizoaceae), with mature seeds enclosed in their dry capsules, were collected in the Judean Desert near Jericho, Israel, in the summer of 1972, and have been stored dry under room conditions [15–30°C, 15–25% relative humidity (RH)] since then. More than 31 years after maturation, these unimbibed seeds retained an annual rhythm of germination. A significantly higher percentage of seeds originating from the terminal, central and basal parts of the capsules germinated in February or March compared to other months of the year. This phenomenon was repeated in all three groups of seeds in 2001, 2002 and 2003 for germination in darkness at 15°C, and in terminal seeds germinated at 25°C in darkness for 4 years from 2001 to 2004. The annual rhythm of M. nodiflorum germination may regulate the season and percentage of seeds that germinate at the proper time of the year, even after many years. But the open question still remains: how do dry seeds measure time, and what are the mechanisms involved?

1997 ◽  
Vol 161 ◽  
pp. 203-218 ◽  
Author(s):  
Tobias C. Owen

AbstractThe clear evidence of water erosion on the surface of Mars suggests an early climate much more clement than the present one. Using a model for the origin of inner planet atmospheres by icy planetesimal impact, it is possible to reconstruct the original volatile inventory on Mars, starting from the thin atmosphere we observe today. Evidence for cometary impact can be found in the present abundances and isotope ratios of gases in the atmosphere and in SNC meteorites. If we invoke impact erosion to account for the present excess of129Xe, we predict an early inventory equivalent to at least 7.5 bars of CO2. This reservoir of volatiles is adequate to produce a substantial greenhouse effect, provided there is some small addition of SO2(volcanoes) or reduced gases (cometary impact). Thus it seems likely that conditions on early Mars were suitable for the origin of life – biogenic elements and liquid water were present at favorable conditions of pressure and temperature. Whether life began on Mars remains an open question, receiving hints of a positive answer from recent work on one of the Martian meteorites. The implications for habitable zones around other stars include the need to have rocky planets with sufficient mass to preserve atmospheres in the face of intensive early bombardment.


2003 ◽  
Vol 8 (4) ◽  
pp. 4-5
Author(s):  
Christopher R. Brigham ◽  
James B. Talmage

Abstract Permanent impairment cannot be assessed until the patient is at maximum medical improvement (MMI), but the proper time to test following carpal tunnel release often is not clear. The AMA Guides to the Evaluation of Permanent Impairment (AMA Guides) states: “Factors affecting nerve recovery in compression lesions include nerve fiber pathology, level of injury, duration of injury, and status of end organs,” but age is not prognostic. The AMA Guides clarifies: “High axonotmesis lesions may take 1 to 2 years for maximum recovery, whereas even lesions at the wrist may take 6 to 9 months for maximal recovery of nerve function.” The authors review 3 studies that followed patients’ long-term recovery of hand function after open carpal tunnel release surgery and found that estimates of MMI ranged from 25 weeks to 24 months (for “significant improvement”) to 18 to 24 months. The authors suggest that if the early results of surgery suggest a patient's improvement in the activities of daily living (ADL) and an examination shows few or no symptoms, the result can be assessed early. If major symptoms and ADL problems persist, the examiner should wait at least 6 to 12 months, until symptoms appear to stop improving. A patient with carpal tunnel syndrome who declines a release can be rated for impairment, and, as appropriate, the physician may wish to make a written note of this in the medical evaluation report.


Author(s):  
Lisa Irmen ◽  
Julia Kurovskaja

Grammatical gender has been shown to provide natural gender information about human referents. However, due to formal and conceptual differences between masculine and feminine forms, it remains an open question whether these gender categories influence the processing of person information to the same degree. Experiment 1 compared the semantic content of masculine and feminine grammatical gender by combining masculine and feminine role names with either gender congruent or incongruent referents (e.g., Dieser Lehrer [masc.]/Diese Lehrerin [fem.] ist mein Mann/meine Frau; This teacher is my husband/my wife). Participants rated sentences in terms of correctness and customariness. In Experiment 2, in addition to ratings reading times were recorded to assess processing more directly. Both experiments were run in German. Sentences with grammatically feminine role names and gender incongruent referents were rated as less correct and less customary than those with masculine forms and incongruent referents. Combining a masculine role name with an incongruent referent slowed down reading to a greater extent than combining a feminine role name with an incongruent referent. Results thus specify the differential effects of masculine and feminine grammatical gender in denoting human referents.


2005 ◽  
Vol 35 (139) ◽  
pp. 247-266 ◽  
Author(s):  
Hans-Jürgen Bieling

Recent theoretical conceptions of imperialism may be useful correctives against idealising and harmonising views of international interdependency and co-operation. Analytically, however, they are not necessarily helpful. In terms of the EU, they do not really comprehend its particular international role. Despite improved financial and military capacities, the EU represents not yet an imperial power. Instead, it still pursues a rather hegemonic foreign policy approach due to internal economic restrictions, fragmented political sovereignty and the historical experiences of beneficial economic and political co-operation after World War II. Eventually, however, it remains an open question, whether the multilateralist, law-based and co-operative posture of the EU will prevail even under conditions of economic crisis and further military conflicts in the adjacent neighbourhood.


2020 ◽  
pp. 5-27
Author(s):  
S. M. Drobyshevsky ◽  
N. S. Kostrykina ◽  
A. V. Korytin

The problem of efficiency of regional tax expenditures is an actual issue of the fiscal policy and fiscal federalism in Russia. A large fiscal autonomy allows federal subjects to realize a more active tax policy to attract new investments. One cannot claim current fiscal powers of the Russian regions to be wide. However, not all the regions use even existing tax policy instruments. Moreover, out of the regions that use them only few provide incentives to stimulate investment decisions. Others use regional tax measures to support businesses that already have strong positions in the region. And it is an open question whether such tax incentives are efficient. On the other hand, an aggressive tax competition for investors can also be wasteful for regional budgets. In this paper, we calculate indicators that characterize the depth and scope of tax exemptions provided at the regional level. The calculations are based on the open tax statistics. Through the analysis of the tax legislation as well as the economic structure of selected regions, we reveal the inducements of their higher activity: federal regional tax policy, tax competition or benefits for budget-forming companies of the region.


2018 ◽  
Vol 24 (2) ◽  
Author(s):  
VIMLESH KUMAR TIWARI

Performance of developed genotype RMT 08-2 was evaluated in central, eastern and north-eastern states of India under rain-fed condition for quantitative and qualitative traits. It gave highest seed yield over checks in zone III and V. Morphologically plants were erect, medium spreading in nature and primary branches with dichotomous habit. Plants height ranged from 107124 (cm) which matured in 82-112 days. Mature seeds were round in shape and blackish brown in colour. No significant difference between RVT-2 and checks were observed for test weight trait. An average oil yield 485 (kg/h) was recorded over 7 places which was 10% higher than both checks i.e. 14.12% and 11.24% under AICRP trials. Maximum seed yield was obtained on farmers field during 2013-14 and 2014-15 which was 1500 (kg/h) and 1215 (kg/h) that is 33.42% and 26.30% respectively over farmers own seeds. At Morena center, highest seed yield (1753 kg/h) over Bhawani (1512 kg/h) was 15.94% higher than check whereas RVT-2 gave 2245 (kg/h) against Bhawani (1975 kg/h) which was 13.67% higher. DNA finger printing indicated that primers PUT-19, PUT-96, PUT-149, PUT-169, PUT-181 and PUT-271 are useful in generating unique profile of RVT-2 containing 27 bands for its discrimination from other varieties.


2018 ◽  
Vol 24 (1) ◽  
Author(s):  
LAKSHMI CHOUDHARY ◽  
PRABHAWATI PRABHAWATI

Prevalence of soil transmitted helminthes infections in apparently healthy school going children and other 528 people of different districts of Koshi regions of North Bihar were evaluated. Over all incidences of STHs infection was 39.39% during study. High incidence of STH was seen in the rainy season i.e., in the month of July and August, September, significantly higher (P<0.05) .The incidence of Ascaris lumbricoides was highest in the month of August (18.64%). The month of September was 15.25% followed by that of July (14.4%) and October with 10.16%. Also the incidence of hookworm registered the highest incidence in the month of June (19.27%) and lowest in the month of December (4.82%) during the study period. However prevalence of Trichuris trichiura was negligible and it was almost nil in the most of the months but was highest in month of September with 28.57% and lowest in October with 14.00% The climatic factors are responsible for soil transmitted helminthes which are temperature, rainfall and relative humidity. Ascariasis, Trichuriasis and Ancyclostomiasis (Hookworm infection) are found to be endemic in this region.


2019 ◽  
Vol 25 (1) ◽  
Author(s):  
MASROOR ALI KHAN ◽  
KHALID AL GHAMDI ◽  
JAZEM A. MEHYOUB ◽  
RAKHSHAN KHAN

The focus of this study is to find the relationship between El Nino and dengue fever cases in the study area.Mosquito density was recorded with the help of light traps and through aspirators collection. Climate data were obtained from National Meteorology and Environment centre. (Year wise El Nino and La Nina data are according to NOAA & Golden Gate Weather Services). Statistical methods were used to establish the correlation coefficient between different factors. A high significant relationship was observed between Relative Humidity and Dengue fever cases, but Aedes abundance had no significant relationship with either Relative humidity and Temperature. Our conclusion is that the El Nino does not affect the dengue transmission and Aedes mosquito abundance in this region, which is supported by earlier works.


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