A new integrated and homogenized global monthly land surface air temperature dataset for the period since 1900

A new dataset of integrated and homogenized monthly surface air temperature over global land for the period since 1900 [China Meteorological Administration global Land Surface Air Temperature (CMA-LSAT)] is developed. In total, 14 sources have been collected and integrated into the newly developed dataset, including three global (CRUTEM4, GHCN, and BEST), three regional and eight national sources. Duplicate stations are identified, and those with the higher priority are chosen or spliced. Then, a consistency test and a climate outlier test are conducted to ensure that each station series is quality controlled. Next, two steps are adopted to assure the homogeneity of the station series: (1) homogenized station series in existing national datasets (by National Meteorological Services) are directly integrated into the dataset without any changes (50% of all stations), and (2) the inhomogeneities are detected and adjusted for in the remaining data series using a penalized maximal t test (50% of all stations). Based on the dataset, we re-assess the temperature changes in global and regional areas compared with GHCN-V3 and CRUTEM4, as well as the temperature changes during the three periods of 1900–2014, 1979–2014 and 1998–2014. The best estimates of warming trends and there 95% confidence ranges for 1900–2014 are approximately 0.102 ± 0.006 °C/decade for the whole year, and 0.104 ± 0.009, 0.112 ± 0.007, 0.090 ± 0.006, and 0.092 ± 0.007 °C/decade for the DJF (December, January, February), MAM, JJA, and SON seasons, respectively. MAM saw the most significant warming trend in both 1900–2014 and 1979–2014. For an even shorter and more recent period (1998–2014), MAM, JJA and SON show similar warming trends, while DJF shows opposite trends. The results show that the ability of CMA-LAST for describing the global temperature changes is similar with other existing products, while there are some differences when describing regional temperature changes

Complex Adaptations Can Drive the Evolution of the Capacitor [PSI+], Even with Realistic Rates of Yeast Sex

The [PSI+] prion may enhance evolvability by revealing previously cryptic genetic variation, but it is unclear whether such evolvability properties could be favored by natural selection. Sex inhibits the evolution of other putative evolvability mechanisms, such as mutator alleles. This paper explores whether sex also prevents natural selection from favoring modifier alleles that facilitate [PSI+] formation. Sex may permit the spread of “cheater” alleles that acquire the benefits of [PSI+] through mating without incurring the cost of producing [PSI+] at times when it is not adaptive. Using recent quantitative estimates of the frequency of sex in Saccharomyces paradoxus, we calculate that natural selection for evolvability can drive the evolution of the [PSI+] system, so long as yeast populations occasionally require complex adaptations involving synergistic epistasis between two loci. If adaptations are always simple and require substitution at only a single locus, then the [PSI+] system is not favored by natural selection. Obligate sex might inhibit the evolution of [PSI+]-like systems in other species

Brief Report - Abnormal Doppler Flow Velocimetry in the Growth Restricted Foetus as a Predictor for Necrotising Enterocolitis

Background: Obstetric decision- making for the growth restricted foetus has to take into consideration the benefits and risks of waiting for pulmonary maturity and continued exposure to hostile intra-uterine environment. Necrotising Enterocolitis (NEC) results from continued exposure to hostile environment and is an important cause of poor neonatal outcome. Aims: To evaluate the predictive value of abnormal Doppler flow velocimetry of the foetal umbilical artery for NEC and neonatal mortality. Settings and Design: A retrospective study carried out at a tertiary care centre for obstetric and neonatal care. Materials and Method: Seventy-seven neonates with birth weight less than 2000 gm, born over a period of 18 months were studied. These pregnancies were identified as having growth abnormalities of the foetus. Besides other tests of foetal well-being, they were also subjected to Doppler flow velocimetry of the foeto-placental vasculature. Obstetric outcome was evaluated with reference to period of gestation and route of delivery. The neonatal outcome was reviewed with reference to birth weight, Apgar scores and evidence of NEC. Statistical Analysis used: Chi square test. Results: In the group of patients with Absent or Reverse End Diastolic Frequencies (A/R EDF) in the umbilical arteries, positive predictive value for NEC was 52.6%, (RR 30.2; OR 264). The mortality from NEC was 50%. When umbilical artery velocimetry did not show A/REDF, there were no cases of NEC or mortality. Abnormal umbilical or uterine artery flow increased the rate of caesarean section to 62.5% as compared to 17.6% in cases where umbilical artery flow was normal. Conclusion: In antenatally identified pregnancies at risk for foetal growth restriction, abnormal Doppler velocimetry in the form of A/REDF in the umbilical arteries is a useful guide to predict NEC and mortality in the early neonatal period. (J Postgrad Med 2002;48:182-185

Recent changes in extreme rainfall events in Peninsular Malaysia : 1971-2005

This paper assesses recent changes in extremes of annual rainfall in Peninsular Malaysia based on daily rainfall data for ten rain-gauged stations over the period 1971-2005. Eight indices that represent the extreme events are defined and analyzed. Maps of trends for these indices, which are extreme dry spell (XDS), extreme rain sum (XRS), extreme wet day intensities at 95% and 99% percentiles (I95 and I99), proportion of extreme wet day to the total wet day (R95 and R99), and frequency of extreme wet day at 95% and 99% percentiles (N95 and N99), were analyzed based on annual data and seasons. When the indices are evaluated annually, the Mann-Kendall and linear regression trend tests showed increasing trends in the extreme intensity indices (I95 and I99) at two stations. A significant decrease in N99, associated with the frequency of extremely wet days, was observed at 60% of the stations. The change points for these indices are found to occur in the period of the 1980s. There is no significant trend detected for XDS, XRS, and proportion of extreme rainfall over total rainfall amount indices during the period considered in this study. Descriptive analysis of indices during the monsoon period showed that the annual spatial pattern for the peninsula is very much influenced by the northeast monsoon where the highest mean values for majority of the indices occur during this time period