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Intense x-rays are emitted by plasmas formed when sub-nanosecond laser pulses are focused onto materials, Plasmas produced by pulses containing up to 100 J can re-emit over ten percent of the energy as x-rays above about 1.0 keV. These plasmas may be useful flash x-ray sources.
Excessive salt intake is a common feature of Western dietary patterns, and has been associated with important metabolic changes including cerebral redox state imbalance. Considering that little is known about the effect on progeny of excessive salt intake during pregnancy, the present study investigated the effect of a high-salt diet during pregnancy and lactation on mitochondrial parameters and the redox state of the brains of resulting offspring. Adult female Wistar rats were divided into two dietary groups (n 20 rats/group): control standard chow (0·675 % NaCl) or high-salt chow (7·2 % NaCl), received throughout pregnancy and for 7 d after delivery. On postnatal day 7, the pups were euthanised and their cerebellum, hypothalamus, hippocampus, prefrontal and parietal cortices were dissected. Maternal high-salt diet reduced cerebellar mitochondrial mass and membrane potential, promoted an increase in reactive oxygen species allied to superoxide dismutase activation and decreased offspring cerebellar nitric oxide levels. A significant increase in hypothalamic nitric oxide levels and mitochondrial superoxide in the hippocampus and prefrontal cortex was observed in the maternal high-salt group. Antioxidant enzymes were differentially modulated by oxidant increases in each brain area studied. Taken together, our results suggest that a maternal high-salt diet during pregnancy and lactation programmes the brain metabolism of offspring, favouring impaired mitochondrial function and promoting an oxidative environment; this highlights the adverse effect of high-salt intake in the health state of the offspring.
Over the past several years, we have seen many attacks on publicly funded and mandated archaeology in the United States. These attacks occur at the state level, where governors and state legislatures try to defund or outright eliminate state archaeological programs and institutions. We have also seen several attacks at the federal level. Some members of Congress showcase archaeology as a waste of public tax dollars, and others propose legislation to move federally funded or permitted projects forward without consideration of impacts on archaeological resources. These attacks continue to occur, and we expect them to increase in the future. In the past, a vigilant network of historic preservation and archaeological organizations was able to thwart such attacks. The public, however, largely remains an untapped ally. As a discipline, we have not built a strong public support network. We have not demonstrated the value of archaeology to the public, beyond a scattering of educational and informational programs. In this article, we—a group of archaeologists whose work has focused on public engagement—provide a number of specific recommendations on how to build a strong public constituency for the preservation of our nation's archaeological heritage.
Most original studies and all meta-analyses conducted to date converge on the conclusion that patients with schizophrenia display rather generalized neurocognitive deficits. For the present study, we reopen this seemingly closed chapter and examine whether important influences, such as lack of motivation and negative attitudes towards cognitive assessment, result in poorer secondary neuropsychological performance.
A sample of 50 patients with an established diagnosis of schizophrenia were tested for routine neurocognitive assessment and compared to 60 nonclinical volunteers. Before and after the assessment, subjective momentary influences were examined (e.g. motivation, concerns about assessment, fear about poor outcome) for their impact on performance using a new questionnaire called the Momentary Influences, Attitudes and Motivation Impact (MIAMI) on Cognitive Performance Scale.
As expected, patients performed significantly worse than controls on all neurocognitive domains tested (large effect size, on average). However, patients also displayed more subjective momentary impairment, as well as more fears about the outcome and less motivation than controls. Mediation analyses indicated that these influences contributed to (secondary) poorer neurocognitive performance. Differences in neurocognitive scores shrank to a medium effect size, on average, when MIAMI scores were accounted for.
The data argue that performance on measures of neurocognition in schizophrenia are to a considerable extent due to secondary factors. Poor motivation, fears and momentary impairments distinguished patients from controls and these variables heavily impacted performance. Before concluding that neurocognitive deficits in psychiatric patients are present, clinicians should take these confounding influences into account. Although patients with schizophrenia achieved, on average, worse test scores than controls, a large subgroup displayed spared performance.
We report on the progress of our search for highly dispersed pulsars near the Galactic Center at 5 GHz using the 100-m radio telescope in Effelsberg. We also present key aspects of our new survey for millisecond pulsars at 21 cm in parts of the northern sky. This survey will greatly benefit from the L-band multibeam receiver and a new FFT-based backend which are currently under construction at the MPIfR.
A K-band (18-25 GHz) reflected-wave ruby maser (Moore and Clauss 1979) has been borrowed from the National Radio Astronomy Observatory for radio astronomy use on the NASA 64-m antenna of the Deep Space Network at the Tidbinbilla Tracking Station, near Canberra. The purpose of the installation is to provide additional sensitive spectral line, continuum, and VLBI capabilities in the southern hemisphere. Previous measurements at 22.3 GHz (λ = 13.5 mm) determined that the Tidbinbilla 64-m antenna has a peak aperture efficiency of ˜22%, a well-behaved beam shape and consistent pointing (Fourikis and Jauncey 1979). Before installing the maser on the antenna a cooled (circulator) switch was added to provide a beam-switching capability, and a spectral line receiver following the maser was incorporated. The system was assembled and tested at JPL in late 1980 and installed at Tidbinbilla early in 1981. We give here a brief description and present some of the first line observations made in February and March 1981. Extensive line and continuum observations are planned with the present system and a program is under way to determine the telescope pointing characteristics.
We report the status of a search for pulsars in the Galactic Centre, using a completely revised and improved high-sensitivity double-horn system at 4.85-GHz. We also present calculations about the success rate of periodicity searches for such a survey, showing that in contrast to conclusions in recent literature pulsars can be indeed detected at the chosen search frequency.
Delayed feed and water access is known to impair growth performance of day old broiler chickens. Although effects of feed access on growth performance and immune function of broilers have been examined before, effects of dietary composition and its potential interaction with feed access are hardly investigated. This experiment aimed to determine whether moment of first feed and water access after hatch and pre-starter composition (0 to 7 days) affect growth rate and humoral immune function in broiler chickens. Direct fed chickens received feed and water directly after placement in the grow-out facility, whilst delayed fed chickens only after 48 h. Direct and delayed fed chickens received a control pre-starter diet, or a diet containing medium chain fatty acids (MCFA) or fish oil. At 21 days, chickens were immunized by injection of sheep red blood cells. The mortality rate depended on an interaction between feed access and pre-starter composition (P=0.014). Chickens with direct feed access fed the control pre-starter diet had a higher risk for mortality than chickens with delayed feed access fed the control pre-starter diet (16.4% v. 4.2%) whereas the other treatment groups were in-between. BW gain and feed intake till 25 days in direct fed chickens were higher compared with delayed fed chickens, whilst gain to feed ratio was lower. Within the direct fed chickens, the control pre-starter diet resulted in the highest BW at 28 days and the MCFA pre-starter diet the lowest (Δ=2.4%), whereas this was opposite for delayed fed chickens (Δ=3.0%; P=0.033). Provision of MCFA resulted in a 4.6% higher BW gain and a higher gain to feed ratio compared with other pre-starter diets, but only during the period it was provided (2 to 7 days). Minor treatment effects were found for humoral immune response by measuring immunoglobulins, agglutination titers, interferon gamma (IFN-γ), and complement activity. Concluding, current inclusion levels of fish oil (5 g/kg) and MCFA (30 g/kg) in the pre-starter diet appear to have limited (carryover) effects on growth and development, as well as on humoral immune function.
Despite its importance as a public health concern, relatively little is known about the natural course of cannabis use disorders (CUDs). The primary objective of this research was to provide descriptive data on the onset, recovery and recurrence functions of CUDs during the high-risk periods of adolescence, emerging adulthood and young adulthood based on data from a large prospective community sample.
Probands (n = 816) from the Oregon Adolescent Depression Project (OADP) participated in four diagnostic assessments (T1–T4) between the ages of 16 and 30 years, during which current and past CUDs were assessed.
The weighted lifetime prevalence of CUDs was 19.1% with an average onset age of 18.6 years. Although gender was not significantly related to the age of initial CUD onset, men were more likely to be diagnosed with a lifetime CUD. Of those diagnosed with a CUD episode, 81.8% eventually achieved recovery during the study period. Women achieved recovery significantly more quickly than men. The recurrence rate (27.7%) was relatively modest, and most likely to occur within the first 36 months following the offset of the first CUD episode. CUD recurrence was uncommon after 72 months of remission and recovery.
CUDs are relatively common, affecting about one out of five persons in the OADP sample prior to the age of 30 years. Eventual recovery from index CUD episodes is the norm, although about 30% of those with a CUD exhibit a generally persistent pattern of problematic use extending 7 years or longer.
Radio pulsars in relativistic binary systems are unique tools to study the curved space-time around massive compact objects. The discovery of a pulsar closely orbiting the super-massive black hole at the centre of our Galaxy, Sgr A⋆, would provide a superb test-bed for gravitational physics. To date, the absence of any radio pulsar discoveries within a few arc minutes of Sgr A⋆ has been explained by one principal factor: extreme scattering of radio waves caused by inhomogeneities in the ionized component of the interstellar medium in the central 100 pc around Sgr A⋆. Scattering, which causes temporal broadening of pulses, can only be mitigated by observing at higher frequencies. Here we describe recent searches of the Galactic centre region performed at a frequency of 18.95 GHz with the Effelsberg radio telescope.
Although race and ethnic background are known to be important factors in the completion of advance directives, there is a dearth of literature specifically investigating the effect of race and ethnicity on advance directive completion rate after palliative care consultation (PCC).
A chart review of all patients seen by the PCC service in an academic hospital over a 9-month period was performed. Data were compiled using gender, race, ethnicity, religion, and primary diagnosis. For this study, advance directives were defined as: “Do Not Resuscitate” (DNR) and/or “Do Not Intubate” (DNI).
Of the 400 medical records reviewed, 57% of patients were female and 71.3% documented their religion as Christian. The most common documented diagnosis was cancer (39.5%). Forty-seven percent reported their race as white. White patients completed more advance directives than did nonwhite patients both before (25.67% vs. 12.68%) and after (59.36% vs. 40.84%) PCC. There was a significantly higher proportion of whites who signed an advance directive after a PCC than of nonwhites (p = 0.021); of the 139 whites who did not have an advance directive at admission, 63 signed an advance directive after a PCC compared with 186/60 nonwhites (45% vs. 32%, respectively, p = 0.021). Further analysis revealed that African Americans differed from whites in the likelihood of advance directive execution rates pre-PCC, but not post-PCC.
Significance of results:
This study demonstrates the impact of a PCC on the completion of advance directives, on both whites and nonwhites. The PCC Intervention significantly reduced differences between whites and African Americans in completing advance directives, which have been consistently documented in the end-of-life literature.
Within the Herschel key project “The Warm And Dense ISM” (WADI) we systematically observe
a number of prominent photon-dominated regions (PDRs) to measure the impact of varying UV
fields on the energy balance, the chemical and dynamical structure of heated molecular
Acute respiratory infections (ARI) are the leading cause of death worldwide in children aged <5 years, and understanding contributing factors to their seasonality is important for targeting and implementing prevention strategies. In tropical climates, ARI typically peak during the pre-rainy and rainy seasons. One hypothesis is that rainfall leads to more time spent indoors, thus increasing exposure to other people and in turn increasing the risk of ARI. A case-crossover study design in 718 Bangladeshi children aged <5 years was used to evaluate this hypothesis. During a 3-month period with variable rainfall, rainfall was associated with ARI [odds ratio (OR) 2·97, 95% confidence interval (CI) 1·87–4·70]; some evidence of an increased strength of association as household crowding increased was found (⩾3 people/room, OR 3·31, 95% CI 2·03–5·38), but there was a lack of association in some of the most crowded households (⩾5 to <6 people/room, OR 1·55, 95% CI 0·54–4·47). These findings suggest that rainfall may be increasing exposure to crowded conditions, thus leading to an increased risk of ARI, but that additional factors not captured by this analysis may also play a role.