Presence of 1/f noise in the temporal structure of psychoacoustic parameters of natural and urban sounds.

1/f noise or pink noise, which has been shown to be universal in nature, has also been observed in the temporal envelope of music, speech, and environmental sound. Moreover, the slope of the spectral density of the temporal envelope of music has been shown to correlate well to its pleasing, dull, or chaotic character. In this paper, the temporal structure of a number of instantaneous psychoacoustic parameters of environmental sound is examined in order to investigate whether a 1/f temporal structure appears in various types of sound that are generally preferred by people in everyday life. The results show, to some extent, that different categories of environmental sounds have different temporal structure characteristics. Only a number of urban sounds considered and birdsong, generally, exhibit 1/f behavior on short to medium duration time scales, i.e., from 0.1 s to 10 s, in instantaneous loudness and sharpness, whereas a more chaotic variation is found in birdsong at longer time scales, i.e., of 10 s-200 s. The other sound categories considered exhibit random or monotonic variations in the different time scales. In general, this study shows that a 1/f temporal structure is not necessarily present in environmental sounds that are commonly perceived as pleasant

Five years retrospective cohort analysis of treatment outcomes of TB-HIV patients at a PEPFAR/DOTS Centre in South Eastern Nigeria.

Background: Human immunodeficiency virus (HIV) associated tuberculosis (TB) remains a major global public health challenge, with an estimated 1.4 million patients worldwide. Co-infection with HIV leads to challenges in the diagnosis and treatment of patients. Objectives: The aim of this study was to assess treatment outcomes of a cohort of smear positive TB-HIV co-infected patients over a five-year study period. Methods: A retrospective cohort study of 600 smear-positive tuberculosis patients registered at the chest unit of the University of Nigeria Teaching Hospital, Enugu from January 2008 to December 2012 was done. The data was analyzed using SPSS Version 17. Results: One hundred and three (17.2%) of the patients were co-infected with TB/HIV, while 398 (66.3%) and 99 (16.5%) were HIV negative and unknown respectively. Among the co-infected patients, 45(43.7%) were cured as against 222(55.8%) in the TBHIV negatives (Z=4.53, p=0.000, 95%CI= 0.12-0.34). Respectively in the TB-HIV co-infected and TB-HIV negative patients, treatment completed were 21(20.4%) and 71(17.8%) (Z=9.15, p=0.000, 95%= 0.4035-0.60); defaulted 19(18.5%) vs 70 (17.6%) (Z=9.29, p=0.000, 95%CI=0.42-0.60), died 10(9.7%) vs. 6(1.5%) (Z=1.22, p=0.224, 95%CI= -0.0286-0.1086), and failures were 1(0.9%) vs. 7(1.8%) (Z=2.48, p=0.013, 95%CI=0.04-0.10). Treatment success rate was lower in TB-HIV co-infected patients, 64.1% compared to TB-HIV negative patients with 73.6%. Also those that defaulted among the TB-HIV co-infected patients (18.5%) were higher than 17.6% among TB-HIV negative patients, a difference of 0.9%. Conclusion: Findings demonstrate that HIV co-infection affects TB treatment outcomes adversely. Treatment adherence, timely and sustained access to antiretroviral therapy for TB/HIV co-infected patients are important

Carbon foams from emulsion-templated reduced graphene oxide polymer composites: electrodes for supercapacitor devices

Amphiphilic reduced graphene oxide (rGO) is an efficient emulsifier for water-in-divinylbenzene (DVB) high internal phase emulsions. The polymerisation of the continuous DVB phase of the emulsion template and removal of water results in macroporous poly(divinylbenzene) (polyDVB). Subsequent pyrolysis of the poly(DVB) macroporous polymers yields ‘all-carbon’ foams containing micropores alongside emulsion templated-macropores, resulting in hierarchical porosity. The synthesis of carbon foams, or ‘carboHIPEs’, from poly(DVB) produced by polymerisation of rGO stabilised HIPEs provides both exceptionally high surface areas (up to 1820 m2 g−1) and excellent electrical conductivities (up to 285 S m−1), competing with the highest figures reported for carboHIPEs. The use of a 2D carbon emulsifier results in the elimination of post-carbonisation treatments to remove standard inorganic particulate emulsifiers, such as silica particles. It is demonstrated that rGO containing carboHIPEs are good candidates for supercapacitor electrodes where carboHIPEs derived from more conventional polymerised silica-stabilised HIPEs perform poorly. Supercapacitor devices featured a room-temperature ionic liquid electrolyte and electrodes derived from either rGO- or silica-containing poly(DVB)HIPEs demonstrated a maximum specific capacitance of 26 F g−1, an energy density of 5.2 W h kg−1 and a power density of 280 W kg−1

Thermal properties comparison of hybrid CF/FF and BF/FF cyanate ester-based composites

[EN] Insights within thermal expansion, conductivity, and decomposition dependencies with temperature on symmetrical and unsymmetrical layered carbon (CF) or basalt (BF) fabrics in combination with flax fibers (FF) were approached. Driven by commercial application and environmental concerns, the paper draws attention on a modified formula of cyanate ester with a common epoxy resin under an optimized ratio of 70:30 (vol%) as well as on the hybrid reinforcements stacking sequences. Synergetic effects were debated in terms of the CF and BF stacking sequences and corresponding volume fraction followed by comparisons with values predicted by the deployment of hybrid mixtures rules (RoHM/iRoHM). CF hybrid architectures revealed enhanced effective thermophysical properties over their BF counterparts and both over the FF-reinforced polymer composite considered as a reference. Thermal conductivities spread between 0.116 and 0.299 W m-1 K-1 from room temperature up to 250 C on all hybrid specimens, giving rise to an insulator character. Concerning the coefficient of thermal expansion, CF hybrid architectures disclosed values of 1.236 10-6 K-1 and 3.102 10-6 K-1 compared with BF affine exhibiting 4.794 10-6 K-1 and 6.245 10-6 K-1, respectively, with an increase in their volume fraction.The corresponding author gratefully acknowledges the financial assistance of German Academic Exchange Service-DAAD that enabled and supported the internship with Fraunhofer Research Institution for Polymeric Materials and Composites-PYCO, Germany. Many thanks go to Dr. Christian Dreyer and Dr. Maciej Gwiazda for the resin formula and access to the composite manufacturing technology.Motoc, DL.; Ferrándiz Bou, S.; Balart, R. (2018). Thermal properties comparison of hybrid CF/FF and BF/FF cyanate ester-based composites. 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Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Background: Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. // Methods: We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung's disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. // Findings: We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung's disease) from 264 hospitals (89 in high-income countries, 166 in middle-income countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in low-income countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. // Interpretation: Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between low-income, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Improving the ply/interleaf interface in carbon fibre reinforced composites with variable stiffness

Polystyrene-interleaved carbon fibre reinforced epoxy composites exhibiting controllable stiffness have been manufactured. These composites undergo reductions in flexural stiffness of up to 99% when heated above the glass transition temperature Tg of the interleaf layers. Potential applications for such materials include their use in morphing and deployable structures. Flexural tests at room temperature indicated that improvements in adhesion between the polystyrene and CFRP layers are required to prevent premature failure of the composites at low shear stresses. Here we investigate how modification of the interleaf layer improves the interlaminar shear strength of the laminates without affecting the stiffness loss at elevated temperatures. Two poly(styrene-co-maleic anhydride) (SMA) films with different maleic anhydride content were prepared and used as interleaf films. Thick adherend shear tests showed that the adhesion strength more than doubled, while flexural tests showed that composites containing SMA interleafs had more than twice the apparent flexural strength of composites containing pure polystyrene layers at 25 °C and yet still undergo significant reductions in stiffness at elevated temperature