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In the midst of challenges facing affordable, safe and sustainable housing development, there is a continuous increase in the vast amounts of carton papers, melon seed husks, and groundnut shells discarded as waste materials. This is of great concern, especially, as such residues are under-utilised and their improper disposal creates grave problems. Thus, this work was designed to assess the feasibility of solving the emerging problems by valorising the said wastes into value-added products that can be used for building construction. Samples containing varying weight proportions of waste carton paste (WCP) and melon seed husk (MSH) were developed using Topbond as binding agent. Other samples were similarly fabricated but with groundnut shell (GNS) as a component. From the results of tests performed to investigate strength and heat transfer behaviour of each developed sample, it was observed that nailability remained 100% irrespective of the composite formulations adopted. In other cases, the test results varied according to WCP loadings. Though samples containing MSH appeared to be more efficient than their counterparts with GNS content for thermal insulation, the observed differences in the results were statistically insignificant. Aside being sustainable and inexpensive, it was found generally that the afore-mentioned wastes are promising alternative raw materials for production of medium-density panels that are environmentally-friendly and also suitable for use as either ceiling or interior partition boards for effective thermal insulation in buildings. Such undertakings have the potential to minimise the adverse effects that could be caused by the wastes in question.

Due to the problems militating against solid-waste management in developing countries, the disposal of sugarcane leaves is majorly done by burning in an open space. Such practice usually results in environmental pollution due to generation and emission of carbon dioxide. There is need to look into a scientific way of reducing the waste in question and enhance its use in the production of environmentally-friendly, inexpensive, and value-added material. In this work, thermal conductivity (k), bulk density ( $$\rho$$ ), specific heat capacity (C), thermal diffusivity (λ), thermal absorptivity (⍺), thermal inertia (e), water absorption (W.A), flexural strength ( $$\sigma$$ ), and compressive strength (CS) were investigated for compressed boards made of sugarcane (Saccharum Officinarum) leaves. The mean with standard error values obtained for k, $$\rho$$ , C, λ, ⍺, e, W.A, $$\sigma$$ , and CS were (0.0481 ± 0.0004) Wm−1 K−1, (253.558 ± 2.459) kg.m−3, (2140.930 ± 1.356) Jkg−1 K−1, (8.867 ± 0.024) × 10−8m2 s−1, (20.252 ± 0.004) m−1, (161.633 ± 1.421) Jm−2 K−1 s−½, (90.123 ± 0.164) %, (0.263 ± 0.004) Nmm−2, and (0.152 ± 0.006) Nmm−2, respectively. Observably, these values compare favourably with those of already-known conventional ceiling panels. Thus, sugarcane leaf is a potential eco-friendly raw material for the production of thermal insulation boards that are suitable for use as a ceiling for naturally cooled building design, especially, in tropical regions. Doing so can help to minimise the adverse effect resulting from the practice of its disposal by open burning method.

Background Specific heat capacity is one of the prominent and deciding factors for selection of thermal insulation materials in thermal engineering. In recent times, there has been a great advancement in the manufacturing of a variety of advanced materials in order to meet the modern needs for thermal insulation. Unfortunately, certain drawbacks like high cost of procurement, low accuracy, and limited suitability are associated with the current device that can be used to probe the specific heat capacities of thermal insulators. Thus, there is need to devise a means of addressing the situation. A device, named SEUR’s apparatus, was designed, constructed, and used to determine specific heat capacities of some thermal insulators. Measurements were taken on 2 days, and KD2-pro meter was employed to obtain reference values. Results The percentage error values in the specific heat capacity of plastic (solid), asbestos, and paperboard were found to be 0.09%, 0.14%, and 0.13% for day 1 measurements and 0.08%, 0.17%, and 0.13% for day 2 measurements, respectively. Reproducibility values of 7.4%, 6.4%, and 8.2% were obtained for the plastic, asbestos and paperboard, respectively. These values fall within the range for unconditional acceptability of a test device. Conclusion Results obtained with the use of the SEUR’s apparatus are reliable, valid, and of high accuracy. The apparatus is cost-effective and very suitable for use in quick determination of specific heat capacity of porous, non-porous, homogeneous, or heterogeneous thermal insulating materials.

Assorted potential thermal insulators are fabricated nowadays for possible applications in various fields. Unfortunately, drawbacks like selective suitability, unavailability, and expensiveness hinder the progress in the usage of several devices that are efficient and suitable for probing the thermal conductivity values of such materials. Though the observed challenges can be overcome by using the traditional Lee–Charlton’s Disc (TLD) apparatus, a long-time duration is usually required for the set-up to attain steady state. In this work, a modified Lee–Charlton’s Disc (MLD) apparatus set-up has been designed and put to use. The results showed decrements by 65.66% to 71.87% in the steady-state duration when using the MLD apparatus. By employing the MLD apparatus, thermal conductivity values were determined for thermal insulators with thickness of up to about 9.0 mm. The repeatability and reproducibility of the MLD apparatus satisfied the conditions for unconditional acceptability of a test device/method.

This study was designed to assess the possibility of tailoring waste papers and wood dust into composite materials with plaster of Paris (P.O.P) and also determine the suitability of using the developed composites as ceiling panels in building construction. Assorted un-used papers collected as waste materials were processed into waste paper ash (WPA) which was then after utilized like untreated wood dust (UWD) and treated wood dust (TWD) as filler materials to separately, but at similar volumetric proportions, fabricate test samples with P.O.P as matrix. Static angle of repose and major chemical constituents of the fillers were determined. The results of the tests performed on the samples revealed that increase in the proportion of each filler material resulted to decrease in bulk density, thermal conductivity, thermal diffusivity, and flexural strength but increase in percentage water absorption, specific heat capacity, thermal resistance, heat penetration time, and flaking concentration. Sample developed with 36.7 % of the WPA and the one containing 25.0 % of the TWD exhibited impressive performance ability similar to sample fabricated with 18.3 % of the UWD. Though the most significant improvement in thermal insulating ability over the pure P.O.P sample was observed in the case of samples developed with the UWD, it was found that the proportion of each filler material incorporated into the P.O.P matrix can be adjusted to achieve optimum performance desired of the resulting composite panel during its usage as a ceiling in building. From technical–economic point of view, utilizing waste papers and wood dust as raw materials in the production of new and value-added engineering materials, as in the present study, is a promising possibility of reducing the cost of P.O.P for enhancement of affordable housing, thereby meeting the needs of end-users and also ensure minimization of health hazards associated with paper and wood dust wastes.

This work sought to investigate the effect of varying the frequency of an applied electric field on the dielectric constant of raphia hookeri. The aim of the work was to ascertain the suitability of using the sample for engineering applications. It was revealed, from the recorded results, that the dielectric constant of the sample decays exponentially with frequency. Also, greater degree of polarisation was observed with decrease in frequency. Again, as a good thermal insulator, it was revealed that the values of the sample’s dielectric constant compared favourably with those of commonly used conventional dielectric materials. Thus, it is obvious that if put into production cycle, the sample can serve as a low-cost and environmentally friendly material suitable for engineering applications within audio frequency range. This will, in turn, help to provide raw material for electronic industry and also improve the economy.

Uncertainty about the importance of influenza transmission by airborne droplet nuclei generates controversy for infection control. Human challenge-transmission studies have been supported as the most promising approach to fill this knowledge gap. Healthy, seronegative volunteer ‘Donors’ (n = 52) were randomly selected for intranasal challenge with influenza A/Wisconsin/67/2005 (H3N2). ‘Recipients’ randomized to Intervention (IR, n = 40) or Control (CR, n = 35) groups were exposed to Donors for four days. IRs wore face shields and hand sanitized frequently to limit large droplet and contact transmission. One transmitted infection was confirmed by serology in a CR, yielding a secondary attack rate of 2.9% among CR, 0% in IR (p = 0.47 for group difference), and 1.3% overall, significantly less than 16% (p, Author summary Understanding the relative importance of influenza modes of transmission informs strategic use of preventive measures to reduce influenza risk in high-risk settings such as hospitals and is important for pandemic preparedness. Given the increasing evidence from epidemiological modelling, exhaled viral aerosol, and aerobiological survival studies supporting a role for airborne transmission and the potential benefit of respirators (and other precautions designed to prevent inhalation of aerosols) versus surgical masks (mainly effective for reducing exposure to large droplets) to protect healthcare workers, more studies are needed to evaluate the extent of risk posed airborne versus contact and large droplet spray transmission modes. New human challenge-transmission studies should be carefully designed to overcome limitations encountered in the current study. The low secondary attack rate reported herein also suggests that the current challenge-transmission model may no longer be a more promising approach to resolving questions about transmission modes than community-based studies employing environmental monitoring and newer, state-of-the-art deep sequencing-based molecular epidemiological methods.

BACKGROUND: In laboratory animals, exposure to most general anaesthetics leads to neurotoxicity manifested by neuronal cell death and abnormal behaviour and cognition. Some large human cohort studies have shown an association between general anaesthesia at a young age and subsequent neurodevelopmental deficits, but these studies are prone to bias. Others have found no evidence for an association. We aimed to establish whether general anaesthesia in early infancy affects neurodevelopmental outcomes.METHODS: In this international, assessor-masked, equivalence, randomised, controlled trial conducted at 28 hospitals in Australia, Italy, the USA, the UK, Canada, the Netherlands, and New Zealand, we recruited infants of less than 60 weeks' postmenstrual age who were born at more than 26 weeks' gestation and were undergoing inguinal herniorrhaphy, without previous exposure to general anaesthesia or risk factors for neurological injury. Patients were randomly assigned (1:1) by use of a web-based randomisation service to receive either awake-regional anaesthetic or sevoflurane-based general anaesthetic. Anaesthetists were aware of group allocation, but individuals administering the neurodevelopmental assessments were not. Parents were informed of their infants group allocation upon request, but were told to mask this information from assessors. The primary outcome measure was full-scale intelligence quotient (FSIQ) on the Wechsler Preschool and Primary Scale of Intelligence, third edition (WPPSI-III), at 5 years of age. The primary analysis was done on a per-protocol basis, adjusted for gestational age at birth and country, with multiple imputation used to account for missing data. An intention-to-treat analysis was also done. A difference in means of 5 points was predefined as the clinical equivalence margin. This completed trial is registered with ANZCTR, number ACTRN12606000441516, and ClinicalTrials.gov, number NCT00756600.FINDINGS: Between Feb 9, 2007, and Jan 31, 2013, 4023 infants were screened and 722 were randomly allocated: 363 (50%) to the awake-regional anaesthesia group and 359 (50%) to the general anaesthesia group. There were 74 protocol violations in the awake-regional anaesthesia group and two in the general anaesthesia group. Primary outcome data for the per-protocol analysis were obtained from 205 children in the awake-regional anaesthesia group and 242 in the general anaesthesia group. The median duration of general anaesthesia was 54 min (IQR 41-70). The mean FSIQ score was 99·08 (SD 18·35) in the awake-regional anaesthesia group and 98·97 (19·66) in the general anaesthesia group, with a difference in means (awake-regional anaesthesia minus general anaesthesia) of 0·23 (95% CI -2·59 to 3·06), providing strong evidence of equivalence. The results of the intention-to-treat analysis were similar to those of the per-protocol analysis.INTERPRETATION: Slightly less than 1 h of general anaesthesia in early infancy does not alter neurodevelopmental outcome at age 5 years compared with awake-regional anaesthesia in a predominantly male study population.FUNDING: US National Institutes of Health, US Food and Drug Administration, Thrasher Research Fund, Australian National Health and Medical Research Council, Health Technologies Assessment-National Institute for Health Research (UK), Australian and New Zealand College of Anaesthetists, Murdoch Children's Research Institute, Canadian Institutes of Health Research, Canadian Anesthesiologists Society, Pfizer Canada, Italian Ministry of Health, Fonds NutsOhra, UK Clinical Research Network, Perth Children's Hospital Foundation, the Stan Perron Charitable Trust, and the Callahan Estate.

Checkpoint blockade against CTLA-4 or PD-1 has demonstrated that an endogenous immune response can be stimulated to elicit durable regressions in advanced cancer, but these dramatic responses are currently confined to a minority of patients. This outcome is probably due in part to the complex network of immunosuppressive pathways present in advanced tumors, which are unlikely to be overcome by intervention at a single signaling checkpoint, requiring a counter-directed network of pro-immunity signals. Here we demonstrate a combination immunotherapy that recruits a diverse set of innate and adaptive immune effectors, enabling robust elimination of tumor burdens that to our knowledge have not previously been curable by treatments relying on endogenous immunity. Maximal anti-tumor efficacy required four components: a tumor antigen targeting antibody, an extended half-life IL-2, anti-PD-1, and a powerful T-cell vaccine. This combination elicited durable cures in a majority of animals, formed immunological memory in multiple transplanted tumor models, and induced sustained tumor regression in an autochthonous BRrafV600E/Pten-/- melanoma model. Multiple innate immune cell subsets, CD8+ T-cells, and cross-presenting dendritic cells were critical to successful therapy. Treatment induced high levels of intratumoral inflammatory cytokines and immune cell infiltration, enhanced antibody-mediated tumor antigen uptake, and promoted antigen spreading. These results demonstrate the capacity of an elicited endogenous immune response to destroy large, established tumors and elucidate essential characteristics of combination immunotherapies capable of curing a majority of tumors in experimental settings typically viewed as intractable. Citation Format: Kelly Dare Moynihan, Cary Opel, Gregory Szeto, Alice Tzeng, Zhu Eric, Jesse Engreitz, Williams Robert, Kavya Rakhra, Michael Zhang, Adrienne Rothschilds, Sudha Kumari, Ryan L. Kelly, Byron Kwan, Wuhbet Abraham, Kevin Hu, Naveen Mehta, Monique Kauke, Heikyung Suh, Douglas A. Lauffenburger, K. Dane Wittrup, Darrell J. Irvine. Eradication of large established tumors with combination immunotherapy engaging innate and adaptive immunity. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2016 Oct 20-23; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2017;5(3 Suppl):Abstract nr A52.