Relating size and functionality in human social networks through complexity.

Extensive empirical evidence suggests that there is a maximal number of people with whom an individual can maintain stable social relationships (the Dunbar number). We argue that this arises as a consequence of a natural phase transition in the dynamic self-organization among N individuals within a social system. We present the calculated size dependence of the scaling properties of complex social network models to argue that this collective behavior is an enhanced form of collective intelligence. Direct calculation establishes that the complexity of social networks as measured by their scaling behavior is nonmonotonic, peaking around 150, thereby providing a theoretical basis for the value of the Dunbar number. Thus, we establish a theory-based bridge spanning the gap between sociology and psychology.

Comparison of Temperature Readings, Infrared, Non-Contact Thermometer with Contact Digital Thermometer Readings in Children.

BACKGROUND: Body temperature is an important vital sign in clinical practice which can be measured via electronic contact thermometers and infrared non-contact thermometers. OBJECTIVE: To compare temperature readings taken by non contact infrared thermometer with the conventional digital axillary, rectal and oral temperature readings as well as the influence of environmental temperature on noncontact infrared thermometer readings. METHODOLOGY: A prospective study carried out in the Paediatric outpatient clinic of the Rivers State University Teaching Hospital, Nigeria from September 2020 to December 2020. Infrared noncontact forehead and jugular temperatures along with contact axillary, oral and rectal temperatures at a recorded atmospheric temperature and pressure were measured. Data collected was analysed. RESULTS: A total of 247 children aged 1month to 16 years were enrolled, the mean differences of the temperature pairs of contact and non-contact thermometry ranged from 0.45 - 0.77°C (1.64, -1.81°C) 95% LoA. The highest mean difference was found between infrared forehead and axillary [MD; 0.45(1.64,-0.73°C) 95%LoA] temperatures. There was a significant positive correlation between the mean difference of infrared forehead/ rectal temperature and atmospheric temperature (r = 0 .211 p = 0.029). Linear regression model showed that infrared forehead temperature of 37.1°C was equivalent to rectal temperature of 38°C and axillary of 37.4°C which is the standard cut off for fever. Infrared jugular of 37.2°C was equivalent to rectal of 38°C and axillary temperature of 37.4°C was equivalent to infrared jugular of 37.03°C all at a mean atmospheric temperature of 28.3±1.8°C. CONCLUSION: The mean difference by which infrared noncontact thermometry predicts core temperatures may differ based on atmospheric temperature. Infrared non-contact forehead thermometer reading of 37.1°C could be considered as the fever cut off for non-contact forehead thermometry in Nigeria in regions where the mean atmospheric temperature is 28.3±1.8°C.

CONTEXTE: La température corporelle est un signe vital important dans la pratique clinique qui peut être mesurée à l'aide de thermomètres électroniques à contact et de thermomètres infrarouges sans contact. OBJECTIF: Comparer les lectures de température prises par un thermomètre infrarouge sans contact avec les lectures de température axillaire, rectale et buccale numériques conventionnelles, ainsi que l'influence de la température ambiante sur les lectures de thermomètre infrarouge sans contact. MÉTHODOLOGIE: Une étude prospective réalisée dans la clinique pédiatrique ambulatoire du Rivers State University Teaching Hospital, au Nigéria, de septembre 2020 à décembre 2020. Températures infrarouges sans contact du front et de la jugulaire ainsi que des températures axillaire, orale et rectale de contact à une température et une pression atmosphériques enregistrées ont été mesurés. Les données recueillies ont été analysées. RÉSULTATS: Un total de 247 enfants âgés de 1 mois à 16 ans ont été inclus, les différences moyennes des paires de températures de la thermométrie avec contact et sans contact variaient de 0,45 à 0,77°C (1,64, -1,81°C) 95 % LoA. La différence moyenne la plus élevée a été trouvée entre l'infrarouge frontal et axillaire [MD; 0,45 (1,64,-0,73°C) 95 % LoA]. Il y avait une corrélation positive significative entre la différence moyenne de la température infrarouge frontale/rectale et la température atmosphérique (r = 0,211 p = 0,029). Le modèle de régression linéaire a montré que la température frontale infrarouge de 37,1 °C était équivalente à la température rectale de 38 °C et axillaire de 37,4 °C, qui est la valeur seuil standard pour la fièvre. L'infrarouge jugulaire de 37,2°C équivalait à une température rectale de 38°C et la température axillaire de 37,4°C équivalait à l'infrarouge jugulaire de 37,03°C, le tout à une température atmosphérique moyenne de 28,3±1,8°C. CONCLUSION: La différence moyenne par laquelle la thermométrie infrarouge sans contact prédit les températures centrales peut différer en fonction de la température atmosphérique. La lecture du thermomètre frontal infrarouge sans contact de 37,1 °C pourrait être considérée comme le seuil de fièvre pour la thermométrie frontale sans contact au Nigeria dans les régions où la température atmosphérique moyenne est de 28,3 ± 1,8 °C. Mots clés: Thermomètre sans contact, température rectale, température axillaire, buccale, front, jugulaire, température atmosphérique.

Latent variable modeling to develop a robust proxy for sensitive behaviors: application to latrine use behavior and its association with sanitation access in a middle-income country.

BACKGROUND: Globally, diarrhea is a leading cause of child morbidity and mortality. Although latrines are integral for reducing enteric pathogen transmission, several studies have shown no evidence that latrine ownership improved child health. There are a number of explanations for these results. One explanation is that latrine access does not equate to latrine use. Latrine use, however, is difficult to accurately ascertain, as defecation behavior is often stigmatized. To address this measurement issue, we measure latrine use as a latent variable, indicated by a suite of psychosocial variables. METHODS: We administered a survey of 16 defecation-related psychosocial questions to 251 individuals living in rural Ecuador. We applied latent class analysis (LCA) to these data to model the probability of latrine use as a latent variable. To account for uncertainty in predicted latent class membership, we used a pseudo-class approach to impute five different probabilities of latrine use for each respondent. Via regression modeling, we tested the association between household sanitation and each imputed latrine use variable. RESULTS: The optimal model presented strong evidence of two latent classes (entropy = 0.86): consistent users (78%) and inconsistent users (22%), predicted by 5 of our 16 psychosocial variables. There was no evidence of an association between the probability of latrine use, predicted from the LCA, and household access to basic sanitation (OR = 1.1, 95% CI = 0.6-2.1). This suggests that home access to a sanitation facility may not ensure the use of the facility for every family member at all times. CONCLUSION: Effective implementation and evaluation of sanitation programs requires accurate measurement of latrine use. Psychosocial variables, such as norms, perceptions, and attitudes may provide robust proxy-measures. Future longitudinal studies will help to strengthen the use of these surrogate measures, as many of these factors may be subject to secular trends. Additionally, subgroup analyses will elucidate how our  proxy indicators of latrine defecation vary by individual-level characteristics.

The HepHIV 2017 Conference in Malta: joining forces for the earlier diagnosis of HIV and viral hepatitis.

OBJECTIVES: The objective of the article is to provide an overview of the results of the HepHIV 2017 Conference organized by the HIV in Europe initiative under the Maltese EU Presidency in January 2017. METHODS: A thourough review of all conference presentations (oral and poster presentations) was performed to retrieve the key outcomes of the conference. RESULTS: The key result from the conference was a call to action summarising key priorities in HIV and viral hepatitis testing and linkage to care. This included improving monitoring of viral hepatitis and HIV, mixing testing strategies and ensuring policy support. The important contribution and outcomes of EU funded projects OptTEST and EuroHIVEdat was highlighted. CONCLUSION: An integrated approach to earlier testing and linkage to care across diseases is needed in Europe and the HepHIV conferences create an important forum to reach this aim.

Specific suppression of microgliosis cannot circumvent the severe neuropathology in peroxisomal ß-oxidation-deficient mice.

An important hallmark of various neurodegenerative disorders is the proliferation and activation of microglial cells, the resident immune cells of the central nervous system (CNS). Mice that lack multifunctional protein-2 (MFP2), the key enzyme in peroxisomal ß-oxidation, develop excessive microgliosis that positively correlates with behavioral deficits whereas no neuronal loss occurs. However, the precise contribution of neuroinflammation to the fatal neuropathology of MFP2 deficiency remains largely unknown. Here, we first attempted to suppress the inflammatory response by administering various anti-inflammatory drugs but they failed to reduce microgliosis. Subsequently, Mfp2-/- mice were treated with the selective colony-stimulating factor 1 receptor (CSF1R) inhibitor PLX5622 as microglial proliferation and survival is dependent on CSF1R signaling. This resulted in the elimination of >95% of microglia from control mice but only 70% of the expanded microglial population from Mfp2-/- mice. Despite microglial diminution in Mfp2-/- brain, inflammatory markers remained unaltered and residual microglia persisted in a reactive state. CSF1R inhibition did not prevent neuronal dysfunction, cognitive decline and clinical deterioration of Mfp2-/- mice. Collectively, the unaltered inflammatory profile despite suppressed microgliosis concurrent with persevering clinical decline strengthens our hypothesis that neuroinflammation importantly contributes to the Mfp2-/- phenotype.

Sea level extremes and compounding marine heatwaves in coastal Indonesia.

Low-lying island nations like Indonesia are vulnerable to sea level Height EXtremes (HEXs). When compounded by marine heatwaves, HEXs have larger ecological and societal impact. Here we combine observations with model simulations, to investigate the HEXs and Compound Height-Heat Extremes (CHHEXs) along the Indian Ocean coast of Indonesia in recent decades. We find that anthropogenic sea level rise combined with decadal climate variability causes increased occurrence of HEXs during 2010-2017. Both HEXs and CHHEXs are driven by equatorial westerly and longshore northwesterly wind anomalies. For most HEXs, which occur during December-March, downwelling favorable northwest monsoon winds are enhanced but enhanced vertical mixing limits surface warming. For most CHHEXs, wind anomalies associated with a negative Indian Ocean Dipole (IOD) and co-occurring La Niña weaken the southeasterlies and cooling from coastal upwelling during May-June and November-December. Our findings emphasize the important interplay between anthropogenic warming and climate variability in affecting regional extremes.

Investigation of patent foramen ovale as a mechanism for brain metastasis in patients without prior lung involvement.

PURPOSE: The mechanisms of brain metastasis are incompletely understood. Circulating tumor cells travel to the right heart and through the pulmonary circulation, where they may become lung metastases, and can circulate further to the left heart and brain. In patients who develop brain metastases without lung involvement, we hypothesized that cancer cells may travel directly from the right atrium to left atrium via a patent foramen ovale (PFO), akin to paradoxical embolism. If the prevalence of PFO is greater in these individuals compared to the general population (20-30%), PFO may play a role in brain metastasis, and prophylactic closure may provide benefit. Accordingly, we investigated the prevalence of PFO in patients with brain metastases without prior lung involvement. METHODS: We prospectively identified patients with brain metastases from a non-lung primary cancer with no preceding or concurrent lung involvement. Nine eligible participants underwent a transcranial Doppler study with intravenous agitated saline to assess for PFO. RESULTS: Among nine participants, primary cancers were breast (n = 6), upper gastrointestinal (n = 2), and thyroid (n = 1). A positive bubble study was identified in 2/9 (22.2%) participants: one female with breast cancer and one male with duodenal adenocarcinoma. No participants developed lung metastases on subsequent chest imaging. CONCLUSION: In this prospective pilot study, we found a similar prevalence of PFO in patients who developed brain metastases without preceding lung involvement compared to estimates for the general population. Through a larger study is needed, the development of brain metastases in these individuals may primarily reflect tumor-specific biological factors diecting metastasis organotropism.

Chipping away at memory.

Inverse power-law behavior is known to be characteristic of adaptation, learning, and memory. Herein, we propose a phenomenological model of forgetting based on renewal theory that introduces a new psychophysical concept, chipping; discrete events that chip away at chunks of memory and thereby produce forgetting. The neural mechanism producing these chips is the 1/f-noise that is generically produced in complex neuronal networks.

Genetics of Diego blood groups in Guatemalan Indians: use of antiserums to Diego a and Diebo b antigens.

Red blood cells of 255 inhabitants of San Antonio Palopo, an Indian community on the eastern shore of Lake Atitlán, Guatemala, have been typed with antiserum.. to Diego a (Di(a)) and the newly discovered antiserum to Di(b). Individuals with erythrocyte antigenic types Di(a+ b-, Di(a+ b+), and Di(a-b+) have been found, but the type Di(a-b-) has not been encountered. Population frequencies of antigenic types and family studies support the hypothesis that the erythrocyte antigens, Die and Dib, are controlled by two codominant alleles at a single autosomal locus.

Hormone-dependent coactivator binding to a hydrophobic cleft on nuclear receptors.

The ligand-binding domain of nuclear receptors contains a transcriptional activation function (AF-2) that mediates hormone-dependent binding of coactivator proteins. Scanning surface mutagenesis on the human thyroid hormone receptor was performed to define the site that binds the coactivators, glucocorticoid receptor-interacting protein 1 (GRIP1) and steroid receptor coactivator 1 (SRC-1). The residues involved encircle a small surface that contains a hydrophobic cleft. Ligand activation of transcription involves formation of this surface by folding the carboxyl-terminal alpha helix against a scaffold of three other helices. These features may represent general ones for nuclear receptors.

Chronoamperometric study of conformational relaxation in PPy(DBS).

In conjugated polymer devices that switch from one oxidation level to another, such as artificial muscles, it is important to understand memory effects that stem from conformational relaxation movements of the polymer chains. Chronoamperometry during electrochemical switching of polypyrrole doped with dodecylbenzenesulfonate, PPy(DBS), is used to gain insight into the conformational relaxation processes in cation-transporting materials. During oxidation, the current decays exponentially with a time constant that decreases with the anodic voltage. During reduction, there is again an exponentially decaying current with a time constant that decreases with the cathodic voltage, but superimposed on that is a small current peak that increases in size with the voltage. This peak accounts for a maximum of approximately 20% of the total reduction charge, which is approximately the same amount of charge that is in the most cathodic pair of peaks in the cyclic voltammogram. The position of this peak depends logarithmically on the applied cathodic potential (shifting to shorter times with larger Eca) as well as on the anodic potential that was applied just prior to the reduction step (shifting to longer times with Ean). Furthermore, the shoulder position depends logarithmically on the time that the prior anodic voltage was held (shifting to longer times with twait). These results are consistent with the electrochemically stimulated conformational relaxation (ESCR) model.

Effects of timing of water stress on yield and berry size.

Past irrigation research in Marlborough showed that reducing irrigation on grapes by up to 60% would not have any impact on yield, but that the timing of the irrigation might be important for maintenance of yields. A research trial was set up with Sauvignon blanc grapes planted in containers; periods of water stress were applied for three weeks at different times of the growing season. During the three years of the trial the post-flowering (PO-F) period was consistently most sensitive to water stress. At harvest time, the crop yields for the PO-F water-stressed vines were 55%, 72% and 90% of control yields for the three consecutive years, and the bunch weights were 59%, 84% and 95%. Berry weights for the PO-F water-stressed vines were 87%, 96% and 73% of the control values, although the second-year difference was not significant. In two years out of three, there was a trend for PO-F and pre-veraison (PR-V) water-stressed vines to have the lowest berry soluble solids contents ( degrees Brix), indicating a delay in maturity. We suggest that to use irrigation sustainably, it is safe to reduce water applications for most of the season, but that immediately after flowering, any water stress should be avoided. During the period leading up to veraison, some mild water stress can be applied.

Patterns of violence and coercion with mental health among female and male trafficking survivors: a latent class analysis with mixture models.

AIMS: Human trafficking is a crime and a human rights violation that involves various and simultaneous traumatic events (sexual and physical violence, coercion). Yet, it is unknown how the patterning of violence and coercion affects the mental health of female and male trafficking survivors. METHODS: We conducted a cross-sectional study using a sample of 1015 female and male survivors of trafficking who received post-trafficking assistance services in Cambodia, Thailand or Vietnam. We assessed symptoms of anxiety and depression with the Hopkins Symptoms Checklist and symptoms of post-traumatic stress disorder (PTSD) with the Harvard Trauma Questionnaire. Violence was measured with questions from the World Health Organization International Study on Women's Health. Latent class analysis (LCA) was used to identify distinct patterns of violence and coercion in females and males. Novel multi-step mixture modelling techniques were employed to assess the association of the emergent classes with anxiety, depression and PTSD in females and males. RESULTS: LCA identified two distinct classes of violence and coercion experiences in females (class I: severe sexual and physical violence and coercion (20%); class II: sexual violence and coercion (80%)) and males (class I: severe physical violence and coercion (41%); class II: personal coercion (59%)). Females in class I had a two-fold increase in the odds of anxiety (OR = 2.10; 95% CI: 1.57-2.81) and PTSD (OR = 2.07; 95% CI: 1.03-4.17) compared with females in class II, but differences in the prevalence of anxiety, depression and PTSD were not significant when comparing males in class I to class II. CONCLUSIONS: Specific patterns of violence and coercion provide a more in-depth understanding of the role of gender in the experience of violence and coercion and its association with mental health in survivors of trafficking. This information could be useful to target comprehensive mental health services for female and male trafficking survivors.

Spousal sexual violence and poverty are risk factors for sexually transmitted infections in women: a longitudinal study of women in Goa, India.

OBJECTIVES: To describe factors associated with incident sexually transmitted infections (STI) in a population-based sample of women in Goa, India. METHODS: A random sample of women aged 18-45 years was enrolled in Goa from November 2001 to May 2003. All subjects who consented to participate and completed the recruitment procedure were interviewed six and 12 months after recruitment. Incident chlamydia, gonorrhoea or trichomoniasis from vaginal and/or urine specimens were detected using a commercial polymerase chain reaction and the InPouch TV Culture Kit. RESULTS: Of the 2180 women followed up, 64 had an incident STI (incidence of 1.8% in the first six months, and 1.4% in the second six months). Incident STI was associated with low socioeconomic status, marital status, and with concurrent bacterial vaginosis. Incidence was highest among women who were married and exposed to sexual violence (10.9%), were concerned about their husbands' affairs (10.5%), or were separated, divorced or widowed women (11.0%). CONCLUSIONS: Socially disadvantaged women are at increased risk of STI in this population. Sexual intercourse outside marriage was rarely reported in this population, and women are at risk of becoming infected within marriage, especially those with sexual violence. This highlights the vulnerabilities of socially disadvantaged married women in India, and the need for healthcare professionals to screen STI patients for violence, and provide the necessary support. The results also stress the importance of effectively diagnosing and treating married men with STI and promoting safer sex within marriage.

Does misuse lead to a disorder? The misuse of prescription tranquilizer and sedative medications and subsequent substance use disorders in a U.S. longitudinal sample.

OBJECTIVES: We used two waves of National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) data and examined whether the misuse of prescription tranquilizers or sedatives at Wave 1 was associated with either continued misuse, tranquilizer/sedative use disorder, or other substance use disorder (SUD) at Wave 2. METHODS: Prospective data were analyzed from structured diagnostic interviews using the Alcohol Use disorders and Associated Disabilities Interview Schedule: DSM-IV Version (AUDADIS-DSM-IV). A nationally representative sample of 34,653 of U.S. adults, 18years or older at Wave 1 (2001-2002), were re-interviewed at Wave 2 (2004-2005). After applying the survey weights, the sample represented a population that was 52% female, 71% White, 12% Hispanic, 11% African American, 4% Asian and 2% Native American or other. RESULTS: An estimated 79% of adults who engaged in tranquilizer or sedative misuse at Wave 1 had stopped using these drugs at Wave 2. Only a small percentage (4.3%) of misusers at Wave 1 had a tranquilizer or sedative use disorder at Wave 2. However, 45% (45.0%) of misusers at Wave 1 had at least one other SUD at Wave 2. Among those in remission from a sedative or tranquilizer use disorder at Wave 1, 4.8% had a tranquilizer or sedative use disorder while 34.7% had at least one other SUD at Wave 2. CONCLUSIONS: Most adults who engaged in the misuse of prescription tranquilizers or sedatives ceased using within 3years; however, their prior misuse was associated with higher prevalence of having a SUD three years later.

Interaction of a tissue-specific factor with an essential rat growth hormone gene promoter element.

Rat growth hormone (rGH) gene expression is normally restricted to the anterior pituitary. As a model of this tissue specificity, we compared the transient expression of an rGH-chloramphenicol acetyltransferase (CAT) hybrid gene in rGH-producing rat pituitary tumor (GC) cells and in non-rGH-producing rat fibroblast (rat-2) cells. Deletion analysis of the rGH portion of this hybrid gene demonstrated that DNA sequences within 140 base pairs 5' to the rGH gene were sufficient for correct cell type-specific expression. Deletion of an additional 35 base pairs of the rGH 5'-flanking DNA resulted in a loss of expression of the transfected hybrid gene and correlated with the interaction of a putative trans-acting factor with this region of the rGH promoter. This factor was detectable by DNase I footprinting in a crude nuclear extract from GC cells but not from rat-2 cells. Site-directed mutagenesis of the footprint region caused complete loss of expression of a hybrid gene containing 530 base pairs 5' to the rGH gene. Thus, the interaction of this factor, which we term GC2, is likely to be essential for the tissue-specific expression of the rGH gene.

The core promoter region of the tumor necrosis factor alpha gene confers phorbol ester responsiveness to upstream transcriptional activators.

Activators of protein kinase C, such as 12-O-tetradecanoylphorbol 13-acetate (TPA), are known to regulate the expression of many genes, including the tumor necrosis factor alpha (TNF) gene, by affecting the level or activity of upstream transcription factors. To investigate the mechanism whereby TPA activates the TNF promoter, a series of 5'-deletion mutants of the human TNF promoter linked to chloramphenicol acetyltransferase was transfected into U937 human promonocytic cells. TPA produced a 7- to 11-fold activation of all TNF promoters tested, even those promoters truncated to contain only the core promoter with no upstream enhancer elements. The proximal TNF promoter containing only 28 nucleotides upstream and 10 nucleotides downstream of the RNA start site confers TPA activation to a variety of unrelated upstream enhancer elements and transcription factors, including Sp1, CTF/NF1, cyclic AMP-response element, GAL-E1a, and GAL-VP16. The level of activation by TPA depends on the TATA box structure, since the TPA response is greater in promoters containing the sequence TATAAA than in those containing TATTAA or TATTTA. These findings suggest that the core promoter region is a target for gene regulation by second-messenger pathways.

Mutations in the conserved C-terminal sequence in thyroid hormone receptor dissociate hormone-dependent activation from interference with AP-1 activity.

A short C-terminal sequence that is deleted in the v-ErbA oncoprotein and conserved in members of the nuclear receptor superfamily is required for normal biological function of its normal cellular counterpart, the thyroid hormone receptor alpha (T3R alpha). We carried out an extensive mutational analysis of this region based on the crystal structure of the hormone-bound ligand binding domain of T3R alpha. Mutagenesis of Leu398 or Glu401, which are surface exposed according to the crystal structure, completely blocks or significantly impairs T3-dependent transcriptional activation but does not affect or only partially diminishes interference with AP-1 activity. These are the first mutations that clearly dissociate these activities for T3R alpha. Substitution of Leu400, which is also surface exposed, does not affect interference with AP-1 activity and only partially diminishes T3-dependent transactivation. None of the mutations affect ligand-independent transactivation, consistent with previous findings that this activity is mediated by the N-terminal domain of T3R alpha. The loss of ligand-dependent transactivation for some mutants can largely be reversed in the presence of GRIP1, which acts as a strong ligand-dependent coactivator for wild-type T3R alpha. There is excellent correlation between T3-dependent in vitro association of GRIP1 with T3R alpha mutants and their ability to support T3-dependent transcriptional activation. Therefore, GRIP1, previously found to interact with the glucocorticoid, estrogen, and androgen receptors, may also have a role in T3R alpha-mediated ligand-dependent transcriptional activation. When fused to a heterologous DNA binding domain, that of the yeast transactivator GAL4, the conserved C terminus of T3R alpha functions as a strong ligand-independent activator in both mammalian and yeast cells. However, point mutations within this region have drastically different effects on these activities compared to their effect on the full-length T3R alpha. We conclude that the C-terminal conserved region contains a recognition surface for GRIP1 or a similar coactivator that facilitates its interaction with the basal transcriptional apparatus. While important for ligand-dependent transactivation, this interaction surface is not directly involved in transrepression of AP-1 activity.