A Pre-Protostellar Core in L1551

Large field surveys of NH3, C2S, 13CO and C18O in the L1551 dark cloud have revealed a prolate, pre-protostellar molecular core (L1551-MC) in a relatively quiescent region to the northwest of the well-known IRS 5 source. The kinetic temperature is measured to be 9K, the total mass is ~2Msun, and the average particle density is 10^4-10^5 cm^(-3). L1551-MC is 2.25' x 1.11' in projection oriented at a position angle of 133deg. The turbulent motions are on the order of the sound speed in the medium and contain 4% of the gravitational energy, E_{grav}, of the core. The angular momentum vector is projected along the major axis of L1551-MC corresponding to a rotational energy of 2.5E-3(sin i)^(-2)|E_{grav}|. The thermal energy constitutes about a third of |E_{grav}| and the virial mass is approximately equal to the total mass. L1551-MC is gravitationally bound and in the absence of strong, ~160 microgauss, magnetic fields will likely contract on a ~0.3 Myr time scale. The line profiles of many molecular species suggest that the cold quiescent interior is surrounded by a dynamic, perhaps infalling envelope which is embedded within the ambient molecular gas of L1551.Comment: 27 pages, 7 figures, ApJ accepte

Initial validation of a virtual blood draw exposure paradigm for fear of blood and needles

Fear of blood, injections, and needles commonly prevents or delays individuals' receipt of health care, such as vaccines or blood draws. Innovative methods are needed to overcome these fears and reduce anxiety related to activities of this nature. The present study describes initial testing of an arm illusion paradigm that may prove useful during early phases of graded exposure for people with blood and needle fear. Seventy-four undergraduate students aged 18-29 years were tested. In line with study aims, results indicated that the virtual blood draw paradigm promoted strong perceptions of arm ownership and elicited significant changes in physiological indices (blood pressure, heart rate, electrodermal activity, respiratory rate) in response to key procedure elements (e.g., needle insertion). Further, bivariate correlations indicated that individual differences in self-reported blood and needle fear collected prior to the illusion paradigm were significantly associated with presyncopal symptoms reported following the procedure. In regression analyses, self-reported measures of blood and needle fear explained unique variance in presyncopal symptoms even after controlling for general state anxiety. These findings provide initial support for the virtual blood draw paradigm as a promising tool to help provide graded exposure to medical procedures involving needles and blood draw

Gas phase production of NHD2 in L134N

We show analytically that large abundances of NH2D and NHD2 can be produced by gas phase chemistry in the interiors of cold dense clouds. The calculated fractionation ratios are in good agreement with the values that have been previously determined in L134N and suggest that triply-deuterated ammonia could be detectable in dark clouds. Grain surface reactions may lead to similar NH2D and NHD2 enhancements but, we argue, are unlikely to contribute to the deuteration observed in L134N.Comment: 6 pages, 2 figures, uses psfig.sty and emulateapj.sty, to appear in Astrophysical Journal, vol 55

The association between preschool behavioural problems and internalizing difficulties at age 10-12 years

The aim was to study the association between preschool behavioural problems and emotional symptoms in 10- to 12-year-old children. The study was based on the Aarhus Birth cohort, Denmark, and included 1,336 children. Based on the parent-administered preschool behaviour questionnaire (PBQ), we identified three not mutually exclusive preschool behavioural categories: anxious–fearful (n = 146), hyperactive–distractible (n = 98), and hostile–aggressive (n = 170). Children without any known symptoms were considered well adjusted (n = 1,000). Borderline emotional (n = 105) and emotional difficulties (n = 136) were measured at age 10–12 years with the parent-administered strength and difficulties questionnaire (SDQ). Multinomial logistic regression analyses were used to adjust for potential confounding factors. We found that anxious–fearful behaviour and hostile–aggressive preschool behaviour were associated with twice the risk of school-age emotional difficulties. Comorbidity or confounding failed to explain these results. Hyperactive–distractible preschool behaviour was not associated with school-age emotional difficulties. Preschool anxious–fearful behaviour was associated with school-age emotional difficulties, suggesting internalizing symptom stability in some children from early childhood. Preschool hostile–aggressive behaviour was also associated with school-age emotional difficulties, which suggests transformation of one behavioural dimension into another through childhood, and the need to focus on both early internalizing difficulties and hostile–aggressive behaviour as risk factors for later internalizing difficulties

Deuterated Ammonia in Galactic Protostellar Cores

We report on a survey of \nh2d towards protostellar cores in low-mass star formation and quiescent regions in the Galaxy. Twenty-three out of thirty-two observed sources have significant (\gsim 5\sigma) \nh2d emission. Ion-molecule chemistry, which preferentially enhances deuterium in molecules above its cosmological value of \scnot{1.6}{-5} sufficiently explains these abundances. NH2D/NH3 ratios towards Class 0 sources yields information about the ``fossil remnants'' from the era prior to the onset of core collapse and star formation. We compare our observations with predictions of gas-phase chemical networks.Comment: 16 Pages, 7 Figures, Accepted to Ap.J., to appear in the June 20, 2001 editio

The first next-generation sequencing approach to the mitochondrial phylogeny of African monogenean parasites (Platyhelminthes: Gyrodactylidae and Dactylogyridae)

Abstract Background Monogenean flatworms are the main ectoparasites of fishes. Representatives of the species-rich families Gyrodactylidae and Dactylogyridae, especially those infecting cichlid fishes and clariid catfishes, are important parasites in African aquaculture, even more so due to the massive anthropogenic translocation of their hosts worldwide. Several questions on their evolution, such as the phylogenetic position of Macrogyrodactylus and the highly speciose Gyrodactylus, remain unresolved with available molecular markers. Also, diagnostics and population-level research would benefit from the development of higher-resolution genetic markers. We aim to offer genetic resources for work on African monogeneans by providing mitogenomic data of four species (two belonging to Gyrodactylidae, two to Dactylogyridae), and analysing their gene sequences and gene order from a phylogenetic perspective. Results Using Illumina technology, the first four mitochondrial genomes of African monogeneans were assembled and annotated for the cichlid parasites Gyrodactylus nyanzae, Cichlidogyrus halli, Cichlidogyrus mbirizei (near-complete mitogenome) and the catfish parasite Macrogyrodactylus karibae (near-complete mitogenome). Complete nuclear ribosomal operons were also retrieved, as molecular vouchers. The start codon TTG is new for Gyrodactylus and for Dactylogyridae, as is the incomplete stop codon TA for Dactylogyridae. Especially the nad2 gene is promising for primer development. Gene order was identical for protein-coding genes and differed between the African representatives of these families only in a tRNA gene transposition. A mitochondrial phylogeny based on an alignment of nearly 12,500 bp including 12 protein-coding and two ribosomal RNA genes confirms that the Neotropical oviparous Aglaiogyrodactylus forficulatus takes a sister group position with respect to the other gyrodactylids, instead of the supposedly ‘primitive’ African Macrogyrodactylus. Inclusion of the African Gyrodactylus nyanzae confirms the paraphyly of Gyrodactylus. The position of the African dactylogyrid Cichlidogyrus is unresolved, although gene order suggests it is closely related to marine ancyrocephalines. Conclusions The amount of mitogenomic data available for gyrodactylids and dactylogyrids is increased by roughly one-third. Our study underscores the potential of mitochondrial genes and gene order in flatworm phylogenetics, and of next-generation sequencing for marker development for these non-model helminths for which few primers are available

Pervasive refusal syndrome as part of the refusal–withdrawal–regression spectrum: critical review of the literature illustrated by a case report

Pervasive refusal syndrome (PRS) is a rare child psychiatric disorder characterized by pervasive refusal, active/angry resistance to help and social withdrawal leading to an endangered state. Little has been written about PRS. A literature search yielded only 15 relevant articles, all published between 1991 and 2006. This article presents a critical review of the published literature, illustrated by a case report of an 11-year-old girl. PRS most often affects girls (75%). The mean age of the known population is 10.5 years. A premorbid high-achieving, perfectionist, conscientious personality seems to play an important role in the aetiology of PRS, as can a psychiatric history of parents or child and environmental stressors. PRS shows a symptom overlap with many other psychiatric disorders. However, none of the current DSM diagnoses can account for the full range of symptoms seen in PRS, and the active/angry resistance can be considered as the main distinguishing feature. Treatment should be multidisciplinary and characterized by patience, gentle encouragement and tender loving care. Hospitalization, ideally in a child and adolescent psychiatric unit, is almost always required. Although the recovery process is painfully slow (average duration of therapy 12.8 months), most children recover fully (complete recovery in 67% of known cases). In our opinion, it is important to increase knowledge of PRS, not only because of its disabling, potential life-threatening character, but also because there is hope for recovery through suitable treatment. We therefore propose an incorporation of PRS into the DSM and ICD classifications. However, an adaptation of the current diagnostic criteria is needed. We also consider PRS closely related to regression, which is why we introduce a new concept: “the refusal–withdrawal–regression spectrum”

The Healthy Start project: a randomized, controlled intervention to prevent overweight among normal weight, preschool children at high risk of future overweight

BACKGROUND: Research shows that obesity prevention has to start early. Targeting interventions towards subgroups of individuals who are predisposed, but yet normal weight, may prove more effective in preventing overweight than interventions towards unselected normal weight subsets. Finally, interventions focused on other factors than diet and activity are lacking. The objectives were to perform a randomized, controlled intervention aiming at preventing overweight in children aged 2–6 years, who are yet normal weight, but have high predisposition for future overweight, and to intervene not only by improving diet and physical activity, but also reduce stress and improve sleep quality and quantity. METHODS/DESIGN: Based on information from the Danish National Birth Registry and administrative birth forms, children were selected based on having either a high birth weight, a mother who was overweight prior to pregnancy, or a familial low socioeconomic status. Selected children (n = 5,902) were randomized into three groups; an intervention group, a shadow control group followed in registers exclusively, and a control group examined at the beginning and at the end of the intervention. Approximately 21% agreed to participate. Children who presented as overweight prior to the intervention were excluded from this study (n = 92). In the intervention group, 271 children were included, and in the control group 272 were included. Information obtained from the shadow control group is on-going, but it is estimated that 394 children will be included. The intervention took place over on average 1½ year between 2009 and 2011, and consisted of optional individual guidance in optimizing diet and physical activity habits, reducing chronic stress and stressful events and improving sleep quality and quantity. The intervention also included participation in cooking classes and play arrangements. Information on dietary intake, meal habits, physical activity, sleep habits, and overall stress level was obtained by 4–7 day questionnaire diaries and objective measurements. DISCUSSION: If the Healthy Start project is effective in preventing excessive weight gain, it will provide valuable information on new determinants of obesity which should be considered in future interventions, and on new strategies to prevent development of overweight and obesity at an early age. TRIAL REGISTRATION: ClinicalTrials.gov, ID NCT01583335

Visualizing tephra deposits and sedimentary processes in the marine environment: The potential of X‐ray microtomography

Localized tephra deposition in marine sequences is the product of many complex primary and secondary depositional processes. These can significantly influence the potential applicability of tephra deposits as isochronous marker horizons and current techniques, used in isolation, may be insufficient to fully unravel these processes. Here we demonstrate the innovative application of X-ray microtomography (µCT) to successfully identify tephra deposits preserved within marine sediments and use these parameters to reconstruct their internal three-dimensional structure. Three-dimensional visualizations and animations of tephra dispersal in the sediment permit a more thorough assessment of postdepositional processes revealing a number of complex microsedimentological features that are not revealed by conventional methods. These features include bioturbation burrows and horizontally discontinuous tephra packages, which have important ramifications for the stratigraphic placement of the isochron in a sedimentary sequence. Our results demonstrate the potential for utilizing rigorous two and three-dimensional microsedimentological analysis of the ichnofabric to enhance and support the use of tephra deposits as isochronous marker horizons and to identify the stratigraphic position that best reflects the primary fallout of ash. The application also provides an exceptional insight into the style and rate of sedimentation processes and permits an assessment of the stratigraphic integrity of a tephra deposit. We discuss the possibility of applying these µCT methods to the identification of cryptotephras within various paleoclimatic sequences and to enhance our understanding of marine sedimentation processes

Amplification Free Detection of SARS-CoV-2 Using Multi-valent Binding

[Image: see text] We present the development of electrochemical impedance spectroscopy (EIS)-based biosensors for sensitive detection of SARS-CoV-2 RNA using multi-valent binding. By increasing the number of probe–target binding events per target molecule, multi-valent binding is a viable strategy for improving the biosensor performance. As EIS can provide sensitive and label-free measurements of nucleic acid targets during probe–target hybridization, we used multi-valent binding to build EIS biosensors for targeting SARS-CoV-2 RNA. For developing the biosensor, we explored two different approaches including probe combinations that individually bind in a single-valent fashion and the probes that bind in a multi-valent manner on their own. While we found excellent biosensor performance using probe combinations, we also discovered unexpected signal suppression. We explained the signal suppression theoretically using inter- and intra-probe hybridizations which confirmed our experimental findings. With our best probe combination, we achieved a LOD of 182 copies/μL (303 aM) of SARS-CoV-2 RNA and used these for successful evaluation of patient samples for COVID-19 diagnostics. We were also able to show the concept of multi-valent binding with shorter probes in the second approach. Here, a 13-nt-long probe has shown the best performance during SARS-CoV-2 RNA binding. Therefore, multi-valent binding approaches using EIS have high utility for direct detection of nucleic acid targets and for point-of-care diagnostics