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Node movement can be exploited to reduce the energy consumption of wireless network communication. The strategy consists in delaying communication until a mobile node moves close to its target peer node, within an application-imposed deadline. We evaluate the performance of various heuristics that, based on the movement history of the mobile node, estimate an optimal time (in the sense of least energy use) of communication subject to the delay constraint. We evaluate the impact of node movement model, length of movement history maintained, allowable delay, single hop versus multiple hop communication, and size of data transfer on the energy consumption. We also present measurement results on an iPAQ pocket PC that quantify energy consumption in executing the prediction algorithms. Our results show that, with relatively simple and hence efficient prediction heuristics, energy savings in communication can significantly outweigh the energy expenses in executing the prediction algorithms.

The recent widespread screening for phenylketonuria among newborn infants has lead to the recognition that not all instances of hyperphenylalanemia is caused by phenylketonuria (PKU). Thispaper describes enzyme studies in four patients with hyperphenylalanemia.Case 1 is a patient with ‘classical’ PKU. Case 2 is an infant who was found to have a plasma phenylalanine (PPA) of 17 mg% at three weeks who showed ‘mild’ PKU. Case 3 is a 35y-ear-old retarded female with PPA values ranging from 6.6 mg % to 11.6 mg % on a regular diet. Case 4 is an infant with a PPA value of 45 mg % at 4 days and 76.4 mg % at 2 ½ weeks. She was treated with low-phenylalanine diet for 15 months and then returned to a regular diet. For the past 7 months on a regular diet, the PPA has ranged between 4.6 mg % and 10.7 mg %. Cases 3 and 4 may be viewed as hyperphenylalanemia without PKU.Phenylalanine hydroxylase was determined by the method of LaDu and Zannoni and fresh liver obtained by biopsy. The results expressed as μM tyrosine14C formed/Gm protein/45 minutes were as follows:These data suggest that the ‘classical’ and ‘mild’ form of PKU probably have the same basic metabolic lesion. They show that hyperphenylalanemia without PKU is not caused by cofactor deficiency and represents a true ‘partial’ PKU as reflected by slightly elevated PPA, delayed clearance of phenylalanine by tolerance test and decrease of phenylalanine hydroxylase in liver. (APS)

PAULING introduced the term ‘molecular disease’ for the hereditary condition of sickle cell anæmia, in which the clinical signs in both the heterozygous carriers with the sickling trait, and the homozygous patients with the anæmia, are explained by the fraction of abnormal hæmoglobin molecules present1. Only a part of the total hæmoglobin is the abnormal type in the heterozygote with one abnormal gene, whereas nearly all the hæmoglobin is the abnormal type in the homozygote with two abnormal genes. An extension of this concept of molecular disease leads to the prediction that in hereditary diseases associated with the loss of activity of an enzyme, the asymptomatic heterozygotes should be identifiable by having less than the normal amount of the enzyme primarily involved in the disease2.

ObjectiveTo determine the attributable mortality caused by delirium in critically ill patients.DesignProspective cohort study.Setting32 mixed bed intensive care unit in the Netherlands, January 2011 to July 2013.Participants1112 consecutive adults admitted to an intensive care unit for a minimum of 24 hours.ExposuresTrained observers evaluated delirium daily using a validated protocol. Logistic regression and competing risks survival analyses were used to adjust for baseline variables and a marginal structural model analysis to adjust for confounding by evolution of disease severity before the onset of delirium.Main outcome measureMortality during admission to an intensive care unit.ResultsAmong 1112 evaluated patients, 558 (50.2%) developed at least one episode of delirium, with a median duration of 3 days (interquartile range 2-7 days). Crude mortality was 94/558 (17%) in patients with delirium compared with 40/554 (7%) in patients without delirium (P<0.001). Delirium was significantly associated with mortality in the multivariable logistic regression analysis (odds ratio 1.77, 95% confidence interval 1.15 to 2.72) and survival analysis (subdistribution hazard ratio 2.08, 95% confidence interval 1.40 to 3.09). However, the association disappeared after adjustment for time varying confounders in the marginal structural model (subdistribution hazard ratio 1.19, 95% confidence interval 0.75 to 1.89). Using this approach, only 7.2% (95% confidence interval −7.5% to 19.5%) of deaths in the intensive care unit were attributable to delirium, with an absolute mortality excess in patients with delirium of 0.9% (95% confidence interval −0.9% to 2.3%) by day 30. In post hoc analyses, however, delirium that persisted for two days or more remained associated with a 2.0% (95% confidence interval 1.2% to 2.8%) absolute mortality increase. Furthermore, competing risk analysis showed that delirium of any duration was associated with a significantly reduced rate of discharge from the intensive care unit (cause specific hazard ratio 0.65, 95% confidence interval 0.55 to 0.76).ConclusionsOverall, delirium prolongs admission in the intensive care unit but does not cause death in critically ill patients. Future studies should focus on episodes of persistent delirium and its long term sequelae rather than on acute mortality.Trial registrationClinicaltrials.gov NCT01905033.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The characteristics of damage by Ostrinia fumacalis (Guenee) to mungbean, Vigna radiate (L.) Wilczek, were investigated in a series of field and greenhouse experiments. The insect preferred to lay eggs on the lower leaf surface, mostly in the upper one-third of the plant. Most of the larval feeding is confined inside stems, but some larvae are also found in the root and pods. The bigger the stem diameter and longer the internodes, the greater was the O. fumacalis damage. In field trials where corn, Zea mays L., and mungbean were planted side by side, O. fumacalis damage to corn was much greater than to mungbean. Insects raised on corn were heavier and larger than those raised on mungbean. In a field test, the farther the mungbean was planted from O. fumacalis-infested corn, the less was the insect damage in mungbean.

A device of the MINPIM structure is proposed and demonstrated to work as a mixer. It employs two MIS junctions connected face-to face with a reversely biased P-N junction to form two MISS transistors in a series to perform mixing. The device was fabricated in a V grooved structure, and its mixed I-Vcharacteristics are presented.

In this work, the breakover condition of the Shockley diode by the voltage triggering is studied. By replacing the current gain and the multiplication factor with their ac counterparts, an elegant definition of the breakover condition is presented and justified to be more general than previous definitions.

A penalty-perturbation method previously proposed by Westbrook (J. Inst. Maths Applics (1974) 14, 79–82) for the solutions of static bending problems for elastic plates is analysed here. The method replaces the single fourth-order biharmonic equation by a system of three second-order equations which is “singularly” perturbed with respect to a small penalty parameter ɛ. The existence of solutions of the perturbed problem for each ɛ > 0 is established and the behaviour of these solutions as ɛ → 0 0 is studied. In particular, the results show that while these solutions are continuous in ɛ at ɛ = 0, analyticity in ɛ at ɛ = 0 is lost except in special cases.

This paper presents an unsupervised inference method for determining the higher-order structure from sequence data. The method is general, but in this paper it is applied to nucleic acid sequences in determining the secondary (2-D) and tertiary (3-D) structure of the macromolecule. The method evaluates position -position interdependence of the sequence using an information measure known as expected mutual information. The expected mutual information is calculated for each pair of positions and the chi-square test is used to screen statistically significant position pairs. In the calculation of expected mutual information, an unbiased probability estimator is used to overcome the problem associated with zero observation in conserved sites. A selection criterion based on known structural constraints of the strongest interdependent position pairs is applied yielding position pairs most indicative of secondary and tertiary interactions. The method has been tested using tRNA and 5S rRNA sequences with very good results.

High-field electron injection is an attractive tool for investigation of properties of thin dielectric layers. The paper discusses the threshold voltage degradation of complementary metal-oxide-semiconductor (CMOS) devices due to high field oxide stressing. Both the filling of existing oxide hole and electron traps and the generation of new defects, namely bulk electron traps and interface states, are carefully considered. It is shown that monitoring of stress voltage transients during constant-current electron injection into the device gate oxide may be very helpful in understanding degradation phenomena. A qualitative model is proposed to explain different behavior and susceptibility of the threshold voltage of CMOS devices to F-N stress-induced degradation. The model is based on differences in charge trapping and detrapping in different regions of very thin gate oxides under different stress conditions in p-type MOS (PMOS) and n-type MOS (NMOS) transistors.

A switching device has been made using two layers of thin oxide. Two conjugate face-to-face MIS's are used to replace the PN+(or NP+) junctions. The electric I-Vcharacteristics of this MINPIM device measured in experiments are presented in this paper. The experiments show that over-voltage stress may cause the NP junction to avalanche and lead to switching. One or two switchings will occur depending on the oxide layers. The holding voltage is also related to the base width. Proper base biasing may enhance the energy band shift or the minority carrier injection ratio and reduce the breakover voltage or holding voltage, respectively.

The use of capacitive antenna structures to assess process-induced charging damage is well documented. A description of a subset of the SEMATECH process-induced damage effect revealer (SPIDER) module set is given in this report. SPIDER utilizes various sizes and shapes of antenna structures tied to transistors. In this investigation, the evaluation of plasma etch damage, primarily from the gate polysilicon etch, is reported using 0.5 µ m n-channel metal-oxide-semiconductor (NMOS) antenna transistor. Damage appears to occur at the gate oxide bulk and interface. A portion of this damage is not measured after post-metallization annealing unless activated by electrical stress or some subsequent processing. The damage does not correlate with transistor antenna area present during the poly-Si etch. However, a correlation is observed for transistor parameters measured after activation by Fowler-Nordheim stress. This latency may be attributed to hydrogen passivation. A damage model is presented here.