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Nano zinc oxide-decorated graphene (G-ZnO) was blended with polyphenylene sulfide (PPS) to improve its tensile, thermal, crystalline, and barrier properties. The properties of neat PPS and PPS/G-ZnO nanocomposites were characterized and compared using various tests, including tensile tests, scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, evaluation of Escherichia coli inhibition, and barrier performance. The results demonstrated that G-ZnO played a crucial role in heterogeneous nucleation and reinforcement. When the concentration of G-ZnO was 0.3%, the tensile strength, elongation at break, thermostability, crystallinity, and water vapor permeability coefficients (WVPC) approached their maximum values, and the microscopic morphology changed from the original brittle fracture to a relatively tough fracture. In addition, when G-ZnO was added to PPS at a ratio of 0.3%, the tensile strength, elongation at break, and WVPC of PPS were increased by 129%, 150%, and 283%, respectively, compared to pure PPS. G-ZnO endowed the nanocomposites with antibacterial properties. The improvement in barrier performance can be attributed to three reasons: (1) the presence of G-ZnO extended the penetration path of molecules; (2) the coordination and hydrogen bonds between PPS polymer matrix and G-ZnO nanofiller narrowed the H2O transmission path; and (3) due to its more hydrophobic surface, water molecules were less likely to enter the interior of PPS/G-ZnO nanocomposites. This study provides valuable insights for developing high-performance PPS-based nanocomposites for various applications.

Objective: Acute COVID-19 is well-known to cause abnormalities in liver blood tests (LBTs). This study aims to identify what are the long-term implications of COVID-19 on LBTs. Methods: A retrospective cohort study that examined the LBTs of patients admitted with COVID-19 both during acute infection and for up to one year. R factor was used to identify type of liver injury. χ² test and Fisher exact was used for statistical analysis with p5 months post discharge) follow-up, LBT abnormalities were seen in 31.3% and 24% of patients respectively. In both the acute setting and long-term follow-up, cholestatic or mixed injury types were most commonly seen (acute; 41.1%, 41.6% respectively, long-term; 50.0%, 44.4% respectively) . Discussion: Our data suggests that up to one in four patients have persistent LBT abnormalities up to one year following COVID-19. Future research is needed to investigate the clinical signicance of this LBT abnormalities and whether there are interventions, pharmacological or otherwise, that could reduce COVID-19 related liver injury, both in the acute setting, and longer-term. Summary Box: Many studies have shown that acute COVID-19 infection is commonly associated with liver dysfunction in hospitalised patients and even severe liver failure has been noted. Little however has been published about the long term effect of COVID-19 on the liver prole blood tests. This study complements others looking at acute liver dysfunction during COVID-19 suggesting that severity of COVID-19 is a risk factor for liver blood test abnormalities. The study also suggests that younger patients when hospitalised with COVID-19 are more likely to have abnormal liver blood tests compared to their elderly counterparts. However importantly, this study suggests that around a quarter of patient hospitalised with COVID-19 have persistent liver blood test abnormalities up to one year after discharge. This observational study has highlighted the need for further research to investigate the acute and the long-term clinical signicance of LBT abnormalities from COVID-19. This can then help identify whether there are any interventions, pharmacological or otherwise, that could reduce COVID-19 related liver injury, both in the acute setting, and longer-term.

Objective. Dual-modality small animal PET/MR imaging provides temporally correlated information on two biochemical processes of a living object. An magnetic resonance imaging (MRI)-compatible small animal PET insert named Shenzhen Institutes of Advanced Technology (SIAT) aPET was developed by using dual-ended readout depth encoding detectors to simultaneously achieve a uniform high spatial resolution and high sensitivity at the SIAT. In this work, the mutual interferences between SIAT aPET and the 3 T uMR 790 MRI scanner of United Imaging was quantitatively evaluated. Approach. To minimize the mutual interferences, only the PET detectors and the readout electronics were placed inside the MRI scanner, the major signal processing electronic was placed in the corner of the MRI room and the auxiliary unit was placed in the MRI technical room. A dedicated mouse radio fRequency (RF) coil with a transmitter and receiver was developed for the PET insert. The effects of PET scanner on the B 0 and B 1 field of the MRI scanner and the quality of the MRI images were measured. The effects of MRI imaging on the performance of both the PET detectors and scanner were also measured. Main results. The electronic and mechanical components of the PET insert affected the homogeneity of the B 0 field. The PET insert had no effect on the homogeneity of B 1 produced by the dedicated mouse coil but slightly reduced the strength of B 1. The mean and standard deviation of the RF noise map were increased by 2.2% and 11.6%, respectively, while the PET insert was placed in the MRI scanner and powered on. Eddy current was produced while the PET insert was placed in the MRI scanner, and it was further increased while the PET insert was powered on. Despite the above-mentioned interferences from the PET insert, the MR images of a uniform cylindrical water phantom showed that the changes in the signal-to-noise ratio (SNR) and homogeneity as the PET insert was placed in the MRI scanner were acceptable regardless of whether the PET insert was powered off or powered on. The maximum reduction of SNR was less than 11%, and the maximum reduction of homogeneity was less than 2.5% while the PET insert was placed inside the MRI scanner and powered on for five commonly used MRI sequences. MRI using gradient echo (GRE), spin echo (SE) and fast spin echo (FSE) sequences had negligible effects on the flood histograms and energy resolution of the PET detectors, as well as the spatial resolution and sensitivity of the PET scanner. Significance. The mutual interference between the SIAT aPET and the 3 T uMR 790 MRI scanner are acceptable. Simultaneous PET/MRI imaging of small animals can be performed with the two scanners.

Recycled duck bones (DBs) and fish shells were processed into natural derivatives. Through innovative design, these natural derivatives were then combined with biopolymers to create a new type of ecofriendly filament suitable for three-dimensional (3D) printing of scaffolds for bone regeneration. The DBs and fish shells were thermally processed to produce DB-derived hydroxyapatite (HA) and fish shell-derived Ca(OH)2 (TAS), respectively. Poly(ε-caprolactone) (PCL), HA, and TAS were combined and fabricated into new composite filaments, which were then transformed into scaffolds using 3D printing technology. The structure and antibacterial behaviors of the obtained composite scaffolds were studied. Alone, PCL showed no bacterial inhibition. MHA (a mix of HA and TAS) was added to PCL to form a PCL/MHA composite material, which significantly improved the functional properties of PCL and enhanced cell attachment and proliferation. The Ca(OH)2 content of TAS was responsible for the antibacterial effect. The PCL/MHA composites were porous and displayed enhanced osteoblast proliferation in vitro. The osteoblast cell population do not affected when cultured on the PCL/HA and PCL/MHA series composites according to cell cycle distribution analysis. The surfaces of the various PCL/HA and PCL/MHA composites showed elevated levels of calcium and phosphorus compounds when exposed to simulated body fluids. Calcium and phosphate ions were rapidly deposited on PCL/HA and PCL/MHA composite scaffolds in osteoblasts according to the cell mineralization assay. Our findings suggest great potential of the PCL/HA and PCL/MHA composite scaffolds in bone tissue engineering applications.

The performance of small animal PET scanners depends on the energy window (EW) and timing window (TW). In National Electrical Manufacturers Association (NEMA) Standards Publication NU 4-2008, detailed procedures of the performance measurements are defined, but the EW and TW are not specified. In this work, the effects of EW and TW on the physical and imaging performance of Shenzhen Institute of Advanced Technology small animal PET (SIAT aPET) will be evaluated.First, the flood histogram, energy resolution, and timing resolution were measured for a detector of SIAT aPET. Second, the spatial resolutions were measured with different EWs. Third, the sensitivities, the scatter fractions (SFs), and noise equivalent count rates (NECRs) of a mouse-sized phantom and a rat-sized phantom, the recovery coefficients (RCs) of rods of different sizes, and the percentage standard deviation (%STD) of the NEMA image quality phantom were measured for different EWs and TWs. Last, images of a hot rod phantom, a mouse heart, and a rat brain were acquired from the scanner with different EWs.The SIAT aPET detectors provided good flood histograms such that all but the corner crystals can be resolved even with lower energies of 250-350 keV, an average energy resolution of 21.1 ± 1.9%, and an average timing resolution of 2.63 ± 0.69 ns. The average spatial resolutions obtained with EWs of 250-350 keV and 450-550 keV are 0.68 mm and 0.75 mm. For EWs of 250-750 keV, 350-750 keV, and 450-750 keV with a fixed TW of 12 ns, the sensitivities at the center of field of view (FOV) are 16.0%, 11.9%, and 8.2%, the peak NECRs of a mouse-sized phantom are 355.6 kcps, 324.4 kcps, and 249.4 kcps, and the peak NECRs of a rat-sized phantom are 148.5 kcps, 144.3 kcps, and 117.7 kcps, respectively. For the TWs of 4 ns, 8 ns,12 ns, and 20 ns with a fixed EW of 350-750 keV, the sensitivities at the center of FOV are 9.6%, 11.4%, 11.9%, and 12.2%, the peak NECRs of a mouse-sized phantom are 260.1 kcps, 311.5 kcps, 324.4 kcps and 324.9 kcps, and the peak NECRs of a rat-sized phantom are 110.5 kcps, 137.3 kcps, 144.3 kcps, and 142.6 kcps, respectively. Narrowing the EW and TW improves the RCs of rods of all sizes, and the %STD of images obtained with different EWs and TWs are similar. Rods with diameter down to 0.8 mm can be visually resolved from images of the hot rod phantom obtained with different EWs. Images of mouse heart with high spatial resolution and rat brain with detail brain structure were obtained with different EWs. Images of both phantom and in vivo animals obtained with different EWs only showed subtle difference.The performance of SIAT aPET under different EWs and TWs was compared. The EW and TW affect the sensitivity, SF, and NECR but not the spatial resolution and animal images of SIAT aPET, which imply that careful optimization of the EW and TW is not required.

Heat regulation of the human body through textile fabrics is of great interest to the apparel industry. Herein, blends of environmentally friendly materials, including modified polylactic acid (MPLA) (polylactic acid (PLA) + acrylic acid (AA)-grafted PLA (PLA-g-AA) mixed complex) and silica aerogel (SA) composite, were used to make textiles. The tensile, thermal, heat/cold resistance and surface wettability of the novel composites were characterized. MPLA and SA improved the properties of these composites. The MPLA/SA textiles exhibited more favorable mechanical properties than the PLA/SA textiles; this effect was due to better compatibility between the MPLA and SA. Polylactic acid typically exhibits high hydrophilicity and poor thermal conductivity. Incorporating SA as a filler in the processed yarn significantly enhanced the functional performance of the PLA composite textiles. The addition of SA enhanced hydrophobicity and decreased thermal conductivity, which enabled better temperature regulation. The MPLA/SA textiles displayed superior tensile strength, insulation property, temperature adjustment, water resistance, and washing durability. Moreover, the developed MPLA/SA fabric is suitable for mass production and use in various types of textile goods.

The effects of carbon black (CB) content on the mechanical properties, hydrophobicity, electrical conductivity, morphology, and thermodynamic properties of the poly(lactic acid) (PLA/CB) composites were studied. The results showed that adding an appropriate amount of CB improved both the mechanical properties and hydrophobicity of PLA, but an excessive addition of CB reduced the mechanical properties of PLA/CB composites. The conductivity test results showed that when CB content was exceeded than12 wt%, there was no significant changes. The results of analyzing the barrier performance showed that less CB content helped to extend the path of water molecules; thus, the water barrier performance was slightly improved. However, CB and PLA had no chemical bonding reaction, thus, the oxygen permeability was greatly increased with increase of the CB content. The XRD results showed that an appropriate amount of CB could improve the crystallinity of PLA. It was shown by scanning electron microscopy (SEM) inspection that when the filler content increased from 4 to 12 wt%, the cross-sections of the PLA/CB composites became wavy and coarser, indicating that the morphology of the PLA/CB composites was gradually changed and became more and more brittle. Thermogravimetric analysis showed that thermal stability of PLA could be improved when CB ≤ 8 wt%. Differential scanning calorimetry (DSC) analysis showed that the glass transition temperature of PLA/CB composites was slightly higher than that of the pure PLA, whereas the melting temperature was slightly lower than that of the pure PLA. This new composite material with optimized CB content showed excellent properties.

The textbook alkene halogenation reaction establishes straightforward access to vicinal dihaloalkanes. However, robust catalytic methods to perform dihalogenation in a stereoselective manner are lacking, despite the ubiquity of contiguous halogen-bearing stereocentres in natural products, bioactive and pharmaceutical molecules. Here we show that a urea directing moiety judiciously installed on alkenes could anchor the halogen nucleophiles and thus circumvent the regioselectivity issue in this transformation. Additionally, common alkali halides could be used as halogenating reagents. Our organocatalytic strategy granted modular and streamlined access to diverse homo-/hetero-dihalogenation products with exquisite stereo- and regiocontrol, irrespective of the alkene geometry. Pseudoenantiomeric catalysts could relay chiral information in bromofluorination of isomeric alkenes, providing unified access to the full complement of stereoisomers. Extending this synthetic tactic to alkynes culminated in their atroposelective dihalogenation affording axially chiral alkenes. Stereochemical control in the asymmetric dihalogenation of alkenes and alkynes is challenging. Now, an organocatalytic method is developed, whereby installing a urea-directing moiety on these substrates enables their stereo- and regioselective homo- and hetero-dihalogenation.

Objectives Diagnostic tests for SARS-CoV-2 are important for epidemiology, clinical management, and infection control. Limitations of oro-nasopharyngeal real-time PCR sensitivity have been described based on comparisons of single tests with repeated sampling. We assessed SARS-CoV-2 PCR clinical sensitivity using a clinical and radiological reference standard. Methods Between March-May 2020, 2060 patients underwent thoracic imaging and SARS-CoV-2 PCR testing. Imaging was independently double- or triple-reported (if discordance) by blinded radiologists according to radiological criteria for COVID-19. We excluded asymptomatic patients and those with alternative diagnoses that could explain imaging findings. Associations with PCR-positivity were assessed with binomial logistic regression. Results 901 patients had possible/probable imaging features and clinical symptoms of COVID-19 and 429 patients met the clinical and radiological reference case definition. SARS-CoV-2 PCR sensitivity was 68% (95% confidence interval 64–73), was highest 7-8 days after symptom onset (78% (68–88)) and was lower among current smokers (adjusted odds ratio 0.23 (0.12–0.42) p Conclusions In patients with clinical and imaging features of COVID-19, PCR test sensitivity was 68%, and was lower among smokers; a finding that could explain observations of lower disease incidence and that warrants further validation. PCR tests should be interpreted considering imaging, symptom duration and smoking status.

Since May 2022, cases of human monkeypox virus (hMPXV) with human-to-human cross-transmission have significantly increased in nonendemic countries. Our aim was to characterize diagnostic features of patients with confirmed and possible monkeypox to guide future risk stratification and to describe a virtual care model.We performed a retrospective case-control study of 140 patients assessed and screened for suspected monkeypox; on hMPXV polymerase chain reaction testing, 70 were confirmed positive, and 70 were negative. Data were compared to generate odds ratios of demographic and clinical features.Patients who tested positive were predominantly cis-male (99%) and self-identified as gay, bisexual, and other men who have sex with men (94%). Lymphadenopathy at presentation was associated with a higher likelihood of a positive result (odds ratio [OR] 7.69 [95% confidence interval (CI) 3.58, 16.51]). Patients who tested positive were more likely to have a rash affecting the genital (OR 5.38 [95% CI 2.57, 11.23]) or buttocks/perianal region (OR 3.79 [1.70, 8.45]) than negative controls. A total of 79% of patients were engaged with a virtual ward follow-up.These data can inform a risk-based approach to the management of suspected monkeypox in gay, bisexual, and other men who have sex with men populations. Lymphadenopathy at presentation and the location of the rash were more associated with a positive hMPXV result. Health authorities can consider a virtual ward approach in the hMPHXV outbreak.

Small animal positron emission tomography (PET) scanners are widely used in current biomedical research. The study aimed to develop high-efficiency and ultra-high-resolution detectors that could be used to develop a small animal PET scanner with high sensitivity and spatial resolution approaching to its physical limit.Four crystal arrays were fabricated and measured in this study. Crystal arrays 1 and 2 consisted of 38 × 38 gadolinium aluminum gallium garnet (GAGG) and lutetium-yttrium oxyorthosilicate (LYSO) crystals of 0.4 × 0.4 × 20 mmThe GAGG detectors provided better flood histograms, ∼30% higher photopeak amplitude, ∼20% higher energy resolution, ∼12% worse DOI resolution, and ∼15% worse timing resolution compared with LYSO detectors of the same crystal size. These four detectors provided DOI resolutions of2 mm, energy resolutions of22%, and timing resolutions of1.6 ns. All crystals of 0.4 × 0.4 × 20 mmHigh DOI resolution PET detectors were developed using both GAGG and LYSO arrays with crystal sizes of 0.3 and 0.4 mm, respectively, and a length of 20 mm. The detectors can be used in the future to develop small animal PET scanners, especially dedicated mouse imaging PET scanners, which can simultaneously achieve high sensitivity and ultra-high spatial resolution.

Biodegradable composite from polycaprolactone (PCL) and Graphene/zinc oxide (Graphene/ZnO) is studied. The Graphene/ZnO content is at 0.5%, 1.5% in PCL. Neat PCL and composites were characterized by microstructure, mechanical properties and thermal properties. Scanning electron micrographs show that the additive has agglomerated in PCL/Graphene/ZnO. Agglomeration of the filler results in reduced tensile properties of the composite. The result from XRD indicates Graphene/ZnO can improve the crystallinity of PCL. According to the results of buried soil test and analysis, Graphene/ZnO can reduce the biodegradation rate of PCL and make the material more durable. This new biodegradable composite material can be used as a new environmentally friendly material.

A biodegradable composite nanofiber containing polyhydroxyalkanoate (PHA) or modified PHA (MPHA) and treated fish-scale powder (TFSP) was prepared and characterized. The powder (20-80 nm) was prepared by grinding after treating FSP with water, acid, and heat (450 °C) to yield the TFSP. Composite nanofibers (100-500 nm long) of TFSP/PHA and TFSP/MPHA were fabricated by electrospinning using a biaxial feed method. The TFSP, which had a high hydroxyapatite content, was suitable as a filler for composites. The Ca/P ratio of the TFSP was similar to that of the human bone. Particle size analysis and analysis of scanning electron microscopy images indicated that, compared with the PHA/TFSP composite, the MPHA/TFSP nanofibers were more uniform and bonded more strongly in the matrix. The tensile strength at failure of the MPHA/TFSP specimens was enhanced and increased with increasing TFSP content. The elongation at failure was lower and decreased with increasing TFSP concentration. The water contact angle decreased with increasing TFSP content in PHA/TFSP and MPHA/TFSP nanofiber membranes. The TFSP enhanced the hydrophilic effect of the PHA/TFSP and MPHA/TFSP nanofiber membranes and provided a more suitable environment for cell growth. This composite nanofiber has potential in many biomedical applications.

We report herein new nanofibers prepared from fish scale gelatine (FSG), modified polylactide (MPLA), and a natural antibacterial agent of freshwater clam (Corbicula fluminea Estefanía) shell powder (FCSP). A preparation of FSG from Mullet scales is also described. To improve the biocompatibility and antibacterial activity of the non-woven nanofibers, MPLA/FCSP was added to enhance their antibacterial properties. FSG was then combined with MPLA/FCSP using an electrospinning technique to improve the biocompatibility of the as-fabricated 100-500-nm-diameter non-woven MPLA/FCSP/FSG nanofibers. The resulting tensile properties and morphological characteristics indicated enhanced adhesion among FSG, FCSP, and MPLA in the MPLA/FCSP/FSG nanofibers, as well as improved water resistance and tensile strength, compared with the PLA/FSG nanofibers. MTT assay, cell-cycle, and apoptosis analyses showed that both PLA/FSG and MPLA/FCSP/FSG nanofibers had good biocompatibility. Increasing the FSG content in PLA/FSG and MPLA/FCSP/FSG nanofibers enhanced cell proliferation and free-radical scavenging ability, but did not affect cell viability. Quantitative analysis of bacteria inhibition revealed that FCSP imparts antibacterial activity.

The development of green and renewable materials has attracted increasing attention in recent years. Hence, biocomposite-based packaging materials have been investigated to replace petrochemical materials in several industries, such as the food packaging and electronics packaging industries. The tensile and thermal properties of biocomposite-based packaging materials composed of polylactic acid and plant fiber were mainly investigated in the current literature, but fewer studies on the improvement of water resistance and water vapor/oxygen barrier properties of composite materials were performed. Herein, we describe a composite film comprising TBFP [a mixture of bamboo fiber powder (BFP) and silica aerogel powder] that was combined with modified polylactic acid (MPLA) in a melt-mixing process. The structure, morphology, tensile strength, thermal properties, water absorption properties, water vapor/oxygen barrier effect, cytocompatibility, and biodegradability of the composites were characterized. MPLA and TBFP improved the properties of these composites. Fourier transform infrared and X-ray diffraction spectra have shown interfacial adhesion of MPLA/TBFP, resulting in a tighter structure. Hence, the MPLA/TBFP composite had higher elongation at failure (ε), tensile strength at failure (δ), Young's modulus (

A new filler for polyethylene terephthalate (PET) was synthesized by doping carbon black (CB) with nanosilver. Images taken from energy-dispersive X-ray spectrometry and X-ray diffraction validated the synthesis of the filler (nanosilver-doped CB (CB-Ag)). We evaluated the effect of CB-Ag on the mechanical, thermal, and antibacterial properties of the nanocomposites (CB-Ag/PET). Thermogravimetric analyses, morphology, and tensile tests indicated that thermodegradation, crystallization rate, and tensile strength were all improved as a result of filling PET with CB-Ag. Excellent antibacterial properties were imparted to PET nanocomposites, which would be useful for a wide array of industrial applications.

The engineering of biomaterials provides an opportunity for developing new polymeric composites. In this context, the objective of this work is to produce and evaluate fiber obtained from mixtures ...

Modified graphene (MG) incorporated into a matrix of polyvinyl alcohol (PVA) were prepared by a hydrothermal method and ultrasonic dispersion. The effect of high MG content on the properties of composite films was studied. Due to the chemical reaction between MG and PVA, the water resistance and electrical conductivity were improved. The properties of new film and the possibility of its application as conductivity materials were discussed.

Nanocomposites of high-density polyethylene (HDPE) modified with 0.2 phr graphene-zinc oxide (GN-ZnO) exhibited optimal mechanical properties and thermal stability. Two other nano-materials—GN and nano-ZnO—were also used to compare them with GN-ZnO. Increasing the content of GN-ZnO gradually enhanced the antibacterial and barrier properties, but the addition of 0.3 phr GN-ZnO led to agglomeration that caused defects in the nanocomposites. Herein, we investigated the antibacterial and barrier properties of HDPE nanocomposites infused with different nanoparticles (GN, ZnO, GN-ZnO) of varying concentrations. HDPE and the nanoparticles were melt-blended together in a Haake-Buchler Rheomixer to produce a new environment-friendly nano-material with improved physical and chemical properties. The following characterizations were conducted: tensile test, thermogravimetric analysis, morphology, differential scanning calorimetry, X-ray diffraction, antibacterial test, and oxygen and water vapor permeation test. The results showed that the crystallinity of HDPE was affected with the addition of GN-ZnO, and the nanocomposites had effective antibacterial capacity, strong mechanical properties, high thermal stability, and excellent barrier performance. This type of HDPE nanocomposites reinforced with GN-ZnO would be attractive for packaging industries.

Since the inception of research on hollow silica, the use of hollow nanosilica (HNS) as additives in barrier materials has not been reported. In this study, we evaluated the capacity of HNS as an additive in modified polypropylene (MPP). According to X-ray diffraction (XRD), the crystallinity, tensile strength, and thermal stability of MPP/HNS nanocomposite containing 0.1[Formula: see text]phr HNS approached maximum values. Moreover, the nanocomposite had the best performance in terms of water vapor barrier and oxygen resistance. The reasons for the improvement in barrier performance were discussed. Scanning electron microscopy revealed that HNS at a low content dispersed well in MPP. In conclusion, the synthesized HNS can be used as an additive in barrier materials, and it would have potential applications in the fields of food packaging films and storage containers or materials.

Carbon black and Poly(lactic acid) (PLA) were melting blended to prepare conductive nanocomposites, and melamine was used as the compatibilizer. The effects of nanocarbon black (CB) content on mechanical properties, hydrophobicity, electrical crystalline and morphology of PLA/CB nanocomposites were investigated. The results presented that the tensile properties and hydrophobicity of PLA/CB nanocomposites improved simultaneously by adding appropriate amount of CB, but the mechanical properties of PLA/CB nanocomposites decreased by adding too much CB. The conductivity test results showed that there was no significant change after CB content exceeded 12%. This is due to the CB aggregation. XRD results showed that the main crystallization peak of CB increased with the increase of its content, and the addition of CB did not affect the crystal form of PLA.

While clinical environments are highly focused on COVID-19, reports of missed or delayed treatment for conditions that imitate COVID-19, such as pneumonia caused by the fungus Pneumocystis jirovecii, are emerging. Given the uncertain spectrum of COVID-19 presentations and variable sensitivity of laboratory tests for SARS-CoV-2, there is a risk that, without a high index of suspicion, alternative aetiologies may be overlooked while pursuing a diagnosis of COVID-19. The British HIV Association has been calling for the inclusion of HIV testing in all patients admitted to hospital with suspected COVID-19. In this article we reflect on the importance of including HIV testing to prevent avoidable morbidity and mortality in our patients.

Poly(lactic acid) (PLA)/corn stover (CS) composites were prepared by melt blending different proportions of PLA and added CS. PLA was grafted with acrylic acid to improve the compatibility of the matrix with CS. PLA-g-AA interacted well with CS, resulting in a denser composite material with relatively satisfactory hydrophobic properties. The barrier and mechanical properties of composites were studied, and it was found that the barrier and mechanical properties of PLA-g-AA/CS composite materials were significantly improved, especially those with 30 wt% CS provided better tensile properties and elongation at break. The structure at the tensile section of the composite material was observed using SEM. The proper amount of CS had better dispersion in the matrix, and PLA-g-AA could further improve the interfacial bonding force. The crystallization and thermal properties of the composites were analyzed using XRD, DSC, and TGA, and the effect of the CS content on the crystallinity of composites was also studied.

The experiences of people hospitalised with COVID-19 are under-researched. We designed a COVID-19 patient satisfaction survey and collected responses (n=94) during Liverpool’s first wave (April-June 2020). Although care was generally rated highly, including among people of BAME background, sleep-quality and communication about medications and discharge-planning were identified as areas for improvement. In response, we implemented an education and training package for healthcare professionals working on COVID-19 wards. During Liverpool’s second/third COVID-19 wave, survey responses (n=101) suggested improvement in patient satisfaction across all care domains except discharge-planning and sleep-quality. These UK-first findings are informing local strategies to improve COVID-19 care.

Although biocomposites typically display poor performance, this deficiency can be mitigated by incorporating suitable bio-fillers with the base biopolymer. The main objective of this study was to assess the effectiveness of distillers grains and Paphia undulata shell mixture when used as fillers to improve the functional performance of polylactic acid (PLA). The MPLA/TTDGP (modified polylactic acid, MPLA; coupling agent-treated distillers grains powder, TDGP; and P. undulata shell powder heat-treated at 900 °C, TPUSP) and PLA/DGP (polylactic acid/distillers grains powder) composites were prepared via a melting and mixing process, and then their structural, thermal, mechanical and anti-oxidant properties, as well as their biocompatibility and biodegradability, were characterised. Compared with MPLA and PLA, the tensile properties were obviously enhanced in the MPLA/TTDGP and PLA/DGP composites. The tensile strength at failure (δ) and Young's modulus (E) of MPLA/TTDGP were approximately 5–37 and 50–1,200 MPa higher, respectively, than those of PLA/DGP, due to better interfacial adhesion. The water resistance values of the MPLA/TTDGP and PLA/DGP composites were also increased compared with MPLA and PLA. The water resistance was greater in the MPLA/TTDGP composite than the PLA/DGP composite. Both PLA/DGP and MPLA/TTDGP composites displayed good biocompatibility. DGP increased the polyphenol content, and enhanced the antioxidant properties and biodegradability, of the PLA/DGP and MPLA/TTDGP composites, while TPUSP enhanced the antibacterial properties of the MPLA/TTDGP composite.

Both monolithic and semi-monolithic scintillator positron emission tomography (PET) detectors can measure the depth of interaction with single-ended readout. Usually scintillators with a thickness of 10 mm or less are used since the position resolutions of the detectors degrade as the scintillator thickness increases. In this work, the performance of a 20 mm thick long rectangular semi-monolithic scintillator PET detector was measured by using both single-ended and dual-ended readouts with silicon photomultiplier (SiPM) arrays to provide a high detection efficiency. The semi-monolithic scintillator detector consists of nine lutetium–yttrium oxyorthosilicate slices measuring 1.37 × 51.2 × 20 mm3 with erythrocyte sedimentation rate foils of 0.065 mm thickness in between the slices. The SiPM array at each end of the scintillator detector consists of 16 × 4 SiPMs with a pixel size of 3.0 × 3.0 mm2 and a pitch of 3.2 mm. The 64 signals of each SiPM array are processed by using the TOFPET2 application-specific integrated circuit individually. All but the edge slices can be clearly resolved for the detectors with both single-ended and dual-ended readouts. The single-ended readout detector provides an average full width at half maximum (FWHM) Y (continuous direction) position resolution of 2.43 mm, Z (depth direction) position resolution of 4.77 mm, energy resolution of 25.7% and timing resolution of 779 ps. The dual-ended readout detector significantly improves the Y and Z position resolutions, slightly improves the energy and timing resolution at the cost of two photodetectors required for one detector module and provides an average FWHM Y position resolution of 1.97 mm, Z position resolution of 2.60 mm, energy resolution of 21.7% and timing resolution of 718 ps. The energy and timing resolution of the semi-monolithic scintillator detector in this work are worse than those of the segmented scintillator array detector and need to be further improved. The semi-monolithic scintillator detector described in this work reduces costs as compared to the traditional segmented scintillator array detector and reduces the edge effect as compared to the monolithic scintillator detector.