To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Recent studies have shown the oxygen isotopic composition (δ18O) of modern terrestrial gastropod shells is determined largely by the δ18O of precipitation. This implies that fossil shells could be used to reconstruct the δ18O of paleo-precipitation as long as the isotopic system, including the hydrologic pathways of the local watershed and the gastropod systematics, is well understood. In this study, we measured the δ18O values of 456 individual gastropod shells collected from paleowetland deposits in the San Pedro Valley, Arizona that range in age from ca. 29.1 to 9.8 ka. Isotopic differences of up to 2‰ were identified among the four taxa analyzed (Succineidae, Pupilla hebes, Gastrocopta tappaniana, and Vallonia gracilicosta), with Succineidae shells yielding the highest values and V. gracilicosta shells exhibiting the lowest values. We used these data to construct a composite isotopic record that incorporates these taxonomic offsets, and found shell δ18O values increased by ~4‰ between the last glacial maximum and early Holocene, which is similar to the magnitude, direction, and rate of isotopic change recorded by speleothems in the region. These results suggest the terrestrial gastropods analyzed here may be used as a proxy for past climate in a manner that is complementary to speleothems, but potentially with much greater spatial coverage.
The new standard computerized reading span test (RST), which is a complex verbal working memory test, was used for the first time in the assessment of verbal working memory capacity (Van den Noort et al., 2008) in two clinical populations.
Sixty participants, divided over three different groups; 20 patients with chronic schizophrenia, 20 patients with chronic depression, and 20 healthy participants, entered the study. The selection of the participants was based on strict inclusion and exclusion criteria. There was no comorbid depression in the patients with schizophrenia, as measured by the BDI-II. A comparison was made between the 3 different groups with respect to their verbal working memory capacity. The new standard computerized RST (Van den Noort et al., 2008) was used.
In this study, in line with previous studies, a significant decrease in verbal working memory capacity and a general slowing down was found in chronic patients with schizophrenia and chronic patients with depression in comparison with healthy participants. In addition, patients with schizophrenia showed a nearly significant higher reading span score but were significantly slower than the chronic patients with depression.
The new standard computerized RST (Van den Noort et al., 2008) is a suitable complex verbal working memory test that could be used for clinical applications, for instance, for the assessment of verbal working memory capacity in patients with chronic schizophrenia and chronic depression.
Adult attention deficit hyperactivity disorder (ADHD) has a prevalence up to 4% of the general adult population, however in Spain adult ADHD is underdiagnosed. Screening instruments can help clinicians to detect adult ADHD. The World Health Organization Adult ADHD Self-Report Scale-Version 1.1 (ASRS v1.1) is a 6-question scale designed to screen for adult ADHD.
A validation of Spanish version of the ASRS v1.1 was performed.
A case control study was carry out (adult ADHD vs non ADHD) in the Adult ADHD Program of the Hospital Universitari Vall d'Hebron (Barcelona). ADHD evaluation was performed using Conners Adult ADHD Diagnostic Interview for DSM-IV (CAADID-Part II) and the diagnosis was compared with the ASRS v1.1 responses. Logistic regression study was made to evaluate the sensitivity, specificity, positive and negative predictive values (PPV and NPV). Kappa coefficient of classification accuracy and area under curve (AUC) were calculated.
Sample consisted of 90 adult ADHD and 90 controls. Average age was 31.6 (SD=10.09) and 57.8% of subjects were men (there were no significant differences between the two groups). Logistic regression analysis showed that the score model proposed by the authors of scale is significant (c2 =129.36, p=.0005): Sensitivity (82.2%), specificity (95.6%), PPV (94.8%), NPV (84.3%), Kappa coefficient 0.78 and AUC 0.89.
The Spanish version of the ASRS v1.1 6-question shows adequate psychometric characteristics and it is a valid scale to screen ADHD for adults in a clinical setting.
Attention Deficit Hyperactivity Disorder (ADHD)presents high levels of life-long comorbidity. Several studies demonstrate an elevated coocurrence between ADHD and Substance Use Disorder (SUD) as well as personality disorders.
The objective of this poster is to demonstrate differential characteristics between ADHD with SUD patients versus ADHD without SUD, in relation to Axis II comorbidity, ADHD symptoms severity and childhood behavioural disorders (conduct disorder and oppositional defiant disorder).
Another objective is to identify differences in the prevalence of SUD relative to gender and ADHD subtype (Inattentive, Hyperactive/Impulsive and Combined).
This will be done using a comparative-descriptive study that was carried out with a sample of 125 adults diagnosed with ADHD using the CAADID in the Adult ADHD Integral Programme (PIDAA) of Vall d'Hebron Universitari Hospital; 53 subjects presented associated SUD (DSM-IV). All the subjects were evaluated with ADHD Rating Scale, SCID-I, SCID-II and K-SADS.
Relative to ADHD group, subjects ADHD with SUD subjects showed higher comorbidity with Axis–II Disorders, especially with antisocial, schizoid and paranoid personality disorders, as well as major prevalence of conductual disorder and oppositional defiant disorder in childhood. There were no significant differences respect to ADHD symptoms severity nor ADHD subtype between both groups. A major proportion of men were observed in ADHD with SUD group compared to ADHD patients.
Once daily (q.d.) osmotic release oral system (OROS) methylphenidate has demonstrated to be as efficacious as three times a day (t.i.d.) immediate release (IR) methylphenidate in children with attention deficit hyperactivity disorder (ADHD) but with superior adherence. However, although ADHD continues into adulthood, data in adults are lacking. Effectiveness, adherence to treatment and patient's satisfaction were studied in adults with ADHD before and after switching from methylphenidate IR to OROS presentation.
Seventy newly diagnosed adults with ADHD were treated with t.i.d. methylphenidate IR and, after 3 months, were switched to q.d. OROS formulation and were followed up during 3 additional months. Effectiveness was evaluated with the ADHD Rating Scale (ADHD-RS) and the Clinical Global Impression Improvement (CGI-I) Scale, adherence to treatment with the Simplified Medication Adherence Questionnaire (SMAQ) and patient satisfaction with the treatment. Effectiveness, adherence and satisfaction were compared before and after treatment switch.
ADHD-RS score changed from 34.6 (10.9) at baseline to 25.1 (9.1) while receiving IR methylphenidate and to 15.1 (7.2) while on OROS formulation. Furthermore, methylphenidate switch was associated with an increase of the rate of patients repondents to treatment, from 28.6% to 91.4%. The administration of methylphenidate OROS was associated with better scores in all items of the SMAQ. Methylphenidate OROS was preferred by 97% of patients. All differences were statistically significant. In conclusion, switch from t.i.d. IR to q.d. OROS methylphenidate was associated with an improvement in adherence, patient's satisfaction, and effectiveness.
Mineral phosphorus (P) used to fertilise crops is derived from phosphate rock, which is a finite resource. Preventing and recycling mineral P waste in the food system, therefore, are essential to sustain future food security and long-term availability of mineral P. The aim of our modelling exercise was to assess the potential of preventing and recycling P waste in a food system, in order to reduce the dependency on phosphate rock. To this end, we modelled a hypothetical food system designed to produce sufficient food for a fixed population with a minimum input requirement of mineral P. This model included representative crop and animal production systems, and was parameterised using data from the Netherlands. We assumed no import or export of feed and food. We furthermore assumed small P soil losses and no net P accumulation in soils, which is typical for northwest European conditions. We first assessed the minimum P requirement in a baseline situation, that is 42% of crop waste is recycled, and humans derived 60% of their dietary protein from animals (PA). Results showed that about 60% of the P waste in this food system resulted from wasting P in human excreta. We subsequently evaluated P input for alternative situations to assess the (combined) effect of: (1) preventing waste of crop and animal products, (2) fully recycling waste of crop products, (3) fully recycling waste of animal products and (4) fully recycling human excreta and industrial processing water. Recycling of human excreta showed most potential to reduce P waste from the food system, followed by prevention and finally recycling of agricultural waste. Fully recycling P could reduce mineral P input by 90%. Finally, for each situation, we studied the impact of consumption of PA in the human diet from 0% to 80%. The optimal amount of animal protein in the diet depended on whether P waste from animal products was prevented or fully recycled: if it was, then a small amount of animal protein in the human diet resulted in the most sustainable use of P; but if it was not, then the most sustainable use of P would result from a complete absence of animal protein in the human diet. Our results apply to our hypothetical situation. The principles included in our model however, also hold for food systems with, for example, different climatic and soil conditions, farming practices, representative types of crops and animals and population densities.
Pastoralists have traditional ecological knowledge (TEK), which is important for their livelihoods and for policies and interventions. Pastoralism is under pressure, however, which may result in a decline of pastoral lifestyle and its related TEK. We, therefore, addressed the following objectives (i) to inventorise and assess how pastoralists characterise and value soils and forages in their environment, (ii) to analyse how soil, forage and livestock (i.e. cattle) characteristics relate to herding decisions and (iii) to determine whether TEK underlying herding decisions differs across generations. Data were collected through focus groups and individual interviews with 72 pastoralists, belonging to three generations and to three agro-ecological zones. Using a three-point scale (high, medium, low), four grasses and three tree forages were assessed in terms of nutritional quality for milk, meat, health and strength. Using their own visual criteria, pastoralists identified five different soils, which they selected for herding at different times of the year. Pastoralists stated that Pokuri was the best soil because of its low moisture content, whereas Karaal was the worst because forage hardly grows on it. They stated that perennials, such as Andropogon gayanus and Loxoderra ledermannii, were of high nutritional quality, whereas annuals such as Andropogon pseudapricus and Hyparrhenia involucrata were of low nutritional quality. Afzelia africana was perceived of high quality for milk production, whereas Khaya senegalensis had the highest quality for meat, health and strength. Pastoralists first used soil, then forage and finally livestock characteristics in their herding decisions. Pastoralists’ TEK was not associated with their generations, but with their agro-ecological zones. This study suggests that pastoralists had common and detailed TEK about soils, forages and livestock characteristics, underlying their herding decisions. To conclude, pastoralists use a holistic approach, combining soil, vegetation and livestock TEK in herding decisions. Such TEK can guide restoration or improvement of grazing lands, and land use planning.
Phenylketonuria (PKU), a genetic metabolic disorder that is characterized by the inability to convert phenylalanine to tyrosine, leads to severe intellectual disability and other cerebral complications if left untreated. Dietary treatment, initiated soon after birth, prevents most brain-related complications. A leading hypothesis postulates that a shortage of brain monoamines may be associated with neurocognitive deficits that are observable even in early-treated PKU. However, there is a paucity of evidence as yet for this hypothesis.
We therefore assessed in vivo striatal dopamine D2/3 receptor (D2/3R) availability and plasma monoamine metabolite levels together with measures of impulsivity and executive functioning in 18 adults with PKU and average intellect (31.2 ± 7.4 years, nine females), most of whom were early and continuously treated. Comparison data from 12 healthy controls that did not differ in gender and age were available.
Mean D2/3R availability was significantly higher (13%; p = 0.032) in the PKU group (n = 15) than in the controls, which may reflect reduced synaptic brain dopamine levels in PKU. The PKU group had lower plasma levels of homovanillic acid (p < 0.001) and 3-methoxy-4-hydroxy-phenylglycol (p < 0.0001), the predominant metabolites of dopamine and norepinephrine, respectively. Self-reported impulsivity levels were significantly higher in the PKU group compared with healthy controls (p = 0.033). Within the PKU group, D2/3R availability showed a positive correlation with both impulsivity (r = 0.72, p = 0.003) and the error rate during a cognitive flexibility task (r = 0.59, p = 0.020).
These findings provide further support for the hypothesis that executive functioning deficits in treated adult PKU may be associated with cerebral dopamine deficiency.
Entropic lattice Boltzmann methods were introduced to overcome the stability issues of lattice Boltzmann models for high Reynolds number turbulent flows. However, to date their validity has been investigated only for simple flows due to the lack of appropriate boundary conditions. We present here an extension of these models to complex flows involving curved and moving boundaries in three dimensions. Apart from a thorough investigation of resolved and under-resolved simulations for periodic flow and turbulent flow in a round pipe, we study in detail the set-up of a simplified internal combustion engine with a valve/piston arrangement. This arrangement allows us to probe the non-trivial interactions between various flow features such as jet breakup, jet–wall interaction, and formation and breakup of large vortical structures, among others. Besides an order of magnitude reduction in computational costs, when compared to state-of-the-art direct numerical simulations (DNS), these methods come with the additional advantage of using static Cartesian meshes also for moving objects, which reduces the complexity of the scheme. Going beyond first-order statistics, a detailed comparison of mean and root-mean-square velocity profiles with high-order spectral element DNS simulations and experimental data shows excellent agreement, highlighting the accuracy and reliability of the method for resolved simulations. Moreover, we show that the implicit subgrid features of the entropic lattice Boltzmann method can be utilized to further reduce the grid sizes and the computational costs, providing an alternative to modern modelling approaches such as large-eddy simulations for complex flows.
In this chapter we discuss predictive modeling of series time obtained by functional magnetic resonance imaging (fMRI), representing an important case of spatiotemporal data. Following its development in the early 1990s, fMRI has become a well established approach to investigating brain activity in vivo (Huettel et al. 2004), providing temporally and spatially resolved recordings of the “blood oxygen level dependent” (BOLD) signal of neural tissue. fMRI time series consist of a temporal sequence of scans of the brain and the surrounding space (discretized into voxels), such that the resulting data sets may be stored as vector time series.
The practical work with fMRI time series poses considerable challenges in many aspects, including the huge dimensionality of the data, which usually is recorded from several 10 of voxels, and the plethora of artifacts and contaminations disturbing the data (Strother 2006). Further difficulties arise from the low temporal sampling frequency, typically well below 1 Hz, and the indirect relationship between the BOLD signal and the underlying neural processes.
Currently available approaches to fMRI time series analysis may be broadly classified into three groups:
• exploratory methods, such as cluster analysis (Goutte et al. 1999), principal component analysis (PCA) (Anderson et al. 1999) and independent component analysis (ICA) (McKeown 2000);
• massively univariate (voxel-wise) regression methods, implemented in software packages such as statistical parametric mapping (SPM) (Friston et al. 1994), the FMRIB software library (FSL) (Smith et al. 2004), or the analysis of functional Neuroimages (AFNI) package (Cox 1996);
• generative dynamic models, based on specific assumptions regarding the properties of the underlying neural masses and the biophysical processes which produce the experimental data; as examples we mention dynamic causal modeling (DCM) (Friston et al. 2003) and the hemodynamic state space model (SSM) of Riera et al. (2004a).
Among these three groups of methods, the third may be interpreted as an example of predictive modeling, while for the second group this is possible only in a very limited sense, and essentially impossible for the first group.
On 23 May 2011, CDC identified a multistate cluster of Salmonella Heidelberg infections and two multidrug-resistant (MDR) isolates from ground turkey retail samples with indistinguishable pulsed-field gel electrophoresis patterns. We defined cases as isolation of outbreak strains in persons with illness onset between 27 February 2011 and 10 November 2011. Investigators collected hypothesis-generating questionnaires and shopper-card information. Food samples from homes and retail outlets were collected and cultured. We identified 136 cases of S. Heidelberg infection in 34 states. Shopper-card information, leftover ground turkey from a patient's home containing the outbreak strain and identical antimicrobial resistance profiles of clinical and retail samples pointed to plant A as the source. On 3 August, plant A recalled 36 million pounds of ground turkey. This outbreak increased consumer interest in MDR Salmonella infections acquired through United States-produced poultry and played a vital role in strengthening food safety policies related to Salmonella and raw ground poultry.
The 2013 multistate outbreaks contributed to the largest annual number of reported US cases of cyclosporiasis since 1997. In this paper we focus on investigations in Texas. We defined an outbreak-associated case as laboratory-confirmed cyclosporiasis in a person with illness onset between 1 June and 31 August 2013, with no history of international travel in the previous 14 days. Epidemiological, environmental, and traceback investigations were conducted. Of the 631 cases reported in the multistate outbreaks, Texas reported the greatest number of cases, 270 (43%). More than 70 clusters were identified in Texas, four of which were further investigated. One restaurant-associated cluster of 25 case-patients was selected for a case-control study. Consumption of cilantro was most strongly associated with illness on meal date-matched analysis (matched odds ratio 19·8, 95% confidence interval 4·0–∞). All case-patients in the other three clusters investigated also ate cilantro. Traceback investigations converged on three suppliers in Puebla, Mexico. Cilantro was the vehicle of infection in the four clusters investigated; the temporal association of these clusters with the large overall increase in cyclosporiasis cases in Texas suggests cilantro was the vehicle of infection for many other cases. However, the paucity of epidemiological and traceback information does not allow for a conclusive determination; moreover, molecular epidemiological tools for cyclosporiasis that could provide more definitive linkage between case clusters are needed.
Resistant starch (RS) has been suggested to prolong satiety in adult pigs. The present study investigated RS-induced changes in behaviour, satiety-related hormones and metabolites in catheterized growing pigs to explore possible underlying mechanisms for RS-induced satiety. In a cross-over design with two 14-day periods, 10 pigs (initial BW: 58 kg) were assigned to two treatments comprising diets containing either 35% pregelatinized starch (PS) or 34% retrograded starch (RS). Diets were isoenergetic on gross energy. Pigs were fed at 2.8× maintenance. Postprandial plasma response of satiety-related hormones and metabolites was measured at the end of each period using frequent blood sampling. Faecal and urinary energy losses were measured at the end of each period. Behaviour was scored 24 h from video recordings using scan sampling. Energy digestibility and metabolizability were ~6% lower in RS compared with PS diet (P<0.001), and metabolizable energy (ME) intake was ~3% lower in RS-fed than in PS-fed pigs (P<0.001). RS-fed pigs showed less feeder-directed (P=0.001) and drinking (P=0.10) behaviours than PS-fed pigs throughout the day. Postprandial peripheral short-chain fatty acid (SCFA) levels were higher in RS-fed than in PS-fed pigs (P<0.001). Postprandial glucose and insulin responses were lower in RS-fed than in PS-fed pigs (P<0.001). Triglyceride levels were higher in RS-fed than in PS-fed pigs (P<0.01), and non-esterified fatty acid levels did not differ between diets (P=0.90). Glucagon-like peptide-1 (GLP-1) levels were lower in RS-fed than in PS-fed pigs (P<0.001), and peptide tyrosine tyrosine (PYY) levels did not differ between diets (P=0.90). Blood serotonin levels were lower (P<0.001), whereas monoamine oxidase activity (P<0.05) and tryptophan (P<0.01) levels were higher in RS-fed than in PS-fed pigs. Despite a lower ME intake, RS seemed to prolong satiety, based on behavioural observations. Possible underlying mechanisms for RS-induced satiety include increased 24 h plasma SCFA levels, and decreased postprandial glucose and insulin responses. GLP-1 and PYY seemed not to play a role in RS-induced satiety. Low blood serotonin levels in RS-fed pigs suggested a difference in intestinal serotonin release between treatments. Increased postprandial plasma triglyceride levels corresponded with increased SCFA levels, but it is unclear whether triglycerides may have signalled satiety in RS-fed pigs.
This article presents a set of Late Pleistocene marine mollusk radiocarbon (AMS) age estimates of 30–50 14C kyr BP, whereas a MIS5 age (>75 ka) is indicated by quartz and feldspar OSL dating, biostratigraphy, U-Th dating, and age-depth relationships with sea level. These results indicate that the 14C dates represent minimum ages. The age discrepancy suggests that the shells are contaminated by younger carbon following shell death. The enigmatic 14C dates cannot be “solved” by removing part of the shell by stepwise dissolution. SEM analysis of the Late Pleistocene shells within a context of geologically younger (recent/modern, Holocene) and older (Pliocene) shells shows the presence of considerable amounts of an intracrystalline secondary carbonate precipitate. The presence of this precipitate is not visible using XRD since it is of the same (aragonitic) polymorph as the original shell carbonate. The combination of nanospherulitic-shaped carbonate crystals, typical cavities, and the presence of fatty acids leads to the conclusion that the secondary carbonate, and hence the addition of younger carbon, has a bacterial origin. As shell material was studied, this study recommends an assessment of possible bacterial imprints in other materials like bone collagen as well.
Limited studies exist regarding whether incorporating micronutrient supplements during tuberculosis (TB) treatment may improve cell-mediated immune response. We examined the effect of micronutrient supplementation on lymphocyte proliferation response to mycobacteria or T-cell mitogens in a randomized trial conducted on 423 patients with pulmonary TB. Eligible participants were randomly assigned to receive a daily dose of micronutrients (vitamins A, B-complex, C, E, and selenium) or placebo at the time of initiation of TB treatment. We found no overall effect of micronutrient supplements on lymphocyte proliferative responses to phytohaemagglutinin or purified protein derivatives in HIV-negative and HIV-positive TB patients. Of HIV-negative TB patients, the micronutrient group tended to show higher proliferative responses to concanavalin A than the placebo group, although the clinical relevance of this finding is not readily notable. The role of nutritional intervention in this vulnerable population remains an important area of future research.
Maternal milk is the first source of exogenous polyamines for the newborn. Polyamines modulate gut maturation in neonates, but no studies are available on polyamine concentration in human milk of preterm babies, even though they could be important for their immature gut. The present study aimed to determine polyamine concentration in human breast milk of mothers with preterm or term infants during the first month of lactation. Human milk samples were obtained during the first month of lactation from twenty-seven mothers with preterm babies and twelve mothers with babies born at term. The polyamine concentration in human milk was quantified by HPLC. During the first month of lactation, the total polyamine concentration was significantly higher in preterm milk than in term milk samples (7590 (sd 4990) v. 4660 (sd 4830) nmol/l, respectively (P =0·034)), as well as individual polyamine concentrations. Polyamine concentration in mature milk for preterm babies was significantly higher than that in mature milk for babies at term, and a similar trend was observed in colostrum and transition human milk. The spermidine/spermine ratio was higher in transition milk in preterm v. term samples, while in mature milk, the ratio was significantly lower in preterm than in term babies. In conclusion, the polyamine concentration was significantly higher in human milk for preterm than for term infants. This and the different spermidine/spermine ratios could influence the gut development of premature babies.