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Lack of reliable observational metadata represents a key barrier to understanding sea surface temperature (SST) measurement biases, a large contributor to uncertainty in the global surface record. We present a method to identify SST measurement practice by comparing the observed SST diurnal cycle from individual ships with a reference from drifting buoys under similar conditions of wind and solar radiation. Compared to existing estimates, we found a larger number of engine room‐intake (ERI) reports post–World War II and in the period 1960–1980. Differences in the inferred mixture of observations lead to a systematic warmer shift of the bias adjusted SST anomalies from 1980 compared to previous estimates, while reducing the ensemble spread. Changes in mean field differences between bucket and ERI SST anomalies in the Northern Hemisphere over the period 1955–1995 could be as large as 0.5°C and are not well reproduced by current bias adjustment models. The sea surface temperature (SST) is an important indicator of climate change but its uncertainty affects our confidence in estimates of global surface temperature change. A main systematic component of SST uncertainty (or bias) is caused by changes in SST observational practice onboard ships. Historically, SST measurements have been made either using buckets to collect water samples or recording the temperature of pumped seawater used to cool the ship engines (engine room‐intake (ERI)). Because SST observational biases vary by measurement method, empirical models to quantify SST biases must be applied separately to bucket and ERI SSTs. This approach is hampered by the lack of reliable information on the adopted measurement method. We present an independent assessment of SST measurement practice derived comparing diurnal SST variations from individual ships with those computed from drifting buoys under similar conditions. The newly inferred mixture of observations leads to a systematic warmer shift of the bias‐adjusted SST anomalies from 1980 compared to previous estimates, while reducing the uncertainty in these estimates. Changes in bucket‐ERI mean SST anomaly differences are not fully reproduced by current bias adjustment models. These results have important implications for estimates of uncertainty in SST trends and variability changes. SST measurement method is identified from characteristic differences in diurnal variations under similar wind and solar radiation conditionsMean SST anomaly differences between the different measurement methods vary on scales from global to regional and seasonal to decadalMethod‐dependent bias adjustments used in global SST gridded analyses do not fully capture the observed differences between the methods

We demonstrate interesting and previously unforeseen properties of a pair of gap solitons in a resonant photonic crystal which are predicted and explained in a physically transparent form using both analytical and numerical methods. The most important result is the fact that an oscillating gap soliton created by the presence of a localized population inversion inside the crystal can be manipulated by means of a proper choice of bit rate, phase and amplitude modulation. Developing this idea, we are able to obtain qualitatively different regimes of a resonant photonic crystal operation. In particular, a noteworthy observation is that both the delay time and amplitude difference must exceed a certain level to ensure effective control over the soliton dynamics.

Abstract.: We demonstrate interesting and previously unforeseen properties of a pair of gap solitons in a resonant photonic crystal which are predicted and explained in a physically transparent form using both analytical and numerical methods. The most important result is the fact that an oscillating gap soliton created by the presence of a localized population inversion inside the crystal can be manipulated by means of a proper choice of bit rate, phase and amplitude modulation. Developing this idea, we are able to obtain qualitatively different regimes of a resonant photonic crystal operation. In particular, a noteworthy observation is that both the delay time and amplitude difference must exceed a certain level to ensure effective control over the soliton dynamics.

We demonstrate interesting and previously unforeseen properties of a pair of gap solitons in a resonant photonic crystal which are predicted and explained in a physically transparent form using both analytical and numerical methods. The most important result is the fact that an oscillating gap soliton created by the presence of a localized population inversion inside the crystal can be manipulated by means of a proper choice of bit rate, phase and amplitude modulation. Developing this idea, we are able to obtain qualitatively different regimes of a resonant photonic crystal operation. In particular, a noteworthy observation is that both the delay time and amplitude difference must exceed a certain level to ensure effective control over the soliton dynamics.

Article abstract—

To investigate the relationship between cigarette smoking and Alzheimer's disease (AD) in a prospective community-based study in northern Manhattan.

Seventy-two crossbred steer calves, averaging 61.6 kg in weight and 75 days of age, were divided into two pasture groups. Six calves in each pasture group received one of six estradiol 17βimpregnated silastic rubber implant treatments. Steers receiving treatment 1  were administered a 2.54 cm nonmedicated implant; treatment 2, a 2.54 cm solid; treatment 3, a .64 cm coated; treatment 4, a 1.27 cm coated, treatment 5, a 2.54 cm coated; treatment 6, a 3.81 cm coated implant. Solid refers to estradiol being evenly distributed throughout the implant and coated refers to estradiol being evenly distributed throughout the outer .5 mm of the implant. Subsequent performance of the steer calves was measured during a 169-day suckling phase, a 215-day postweaning growing phase and an 84-day finishing phase. The average calculated estradiol 17βrelease per day during the 468 days was 37.06 µg, 9.01 µg,16.96 µg, 33.04 µg and 49.73 µg for treatments 2  through 6, respectively. During the suckling phase, average daily gains were not different (P>.05) due to treatment. Average daily gains during the growing phase were greater (P<.05) for steers implanted with 2.54 cm solid implants compared to the control and .64 cm implant treated steers. Average growth response, feed intake and carcass characteristics were similar (P>.05) for steers on all treatments during the finishing phase.

We examined the neuropsychological test performance of a randomly selected community sample of English-speaking non-Hispanic African American and white elders in northern Manhattan. All participants were diagnosed as nondemented by a neurologist, whose assessment was made independent of neuropsychological test scores. African American elders obtained significantly lower scores on measures of verbal and nonverbal learning and memory, abstract reasoning, language, and visuospatial skill than whites. After using a stratified random sampling technique to match groups on years of education, many of the discrepancies became nonsignificant; however, significant ethnic group differences on measures of figure memory, verbal abstraction, category fluency, and visuospatial skill remained. Discrepancies in test performance of education-matched African Americans and whites could not be accounted for by occupational attainment or history of medical conditions such as hypertension and diabetes. These findings emphasize the importance of using culturally appropriate norms when evaluating ethnically diverse elderly for dementia.

A paucity of information is available concerning the use of levodopa and carbidopa during pregnancy. Particularly lacking is whether these agents cross the placenta and whether levodopa undergoes metabolism in the fetus. The present study carried out in aborted fetal tissues demonstrates that levodopa crosses the placental barrier and suggests that it may be metabolized in fetal tissues, including the brain and spinal cord. The possibility exists that early exposure to levodopa or dopamine may alter the normal neuronal development in the fetus, and caution in the use of levodopa during pregnancy should be observed.

Summary: Adult male rats were fed a diet containing 0.15% calcium, 0.3% phosphorus, and either 100, 50, or 20 mg of prednisolone per kg of diet. All these levels of prednisolone led to osteopenia, decreased intestinal absorption of calcium, slightly lower serum calcium and phosphorus, and a decreased level of serum 1,25-dihydroxyvitamin D3. Exogenous parenteral 1,25-dihydroxyvitamin D3 corrected steroid-induced changes in serum calcium and phosphorus, but could not completely correct the low intestinal calcium transport; nor did it prevent the development of osteopenia. The prednisolone-induced osteopenia seems at least in part to be caused by impaired intestinal calcium transport. The impaired calcium transport may be the result of low levels of 1,25-dihydroxyvitamin D3 and a direct effect of presnisolone on the intestine.

Although several studies have suggested that hormone replacement therapy lowers the risk of AD among postmenopausal women, few studies have evaluated the relationship of endogenous estrogen levels and AD. The current study investigated whether serum estrone and estradiol levels were related to the presence of AD among postmenopausal women not currently taking hormone replacement therapy.

THE subject has a particular interest for naval architects, inasmuch as the majority of calculations relative to displacement, stability, strength, etc., of ships involve the finding of areas and volumes bounded by curved lines and surfaces.