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The emergence of the COVID-19 pandemic has severely affected medical treatment protocols throughout the world. While the pandemic does not affect hand surgeons at first glance, they have a role to play. The purpose of this study was to describe the different measures that have been put in place in response to the COVID-19 pandemic by hand surgeons throughout the world. The survey comprised 47 surgeons working in 34 countries who responded to an online questionnaire. We found that the protocols varied in terms of visitors, health professionals in the operating room, patient waiting areas, wards and emergency rooms. Based on these preliminary findings, an international consensus on hand surgery practices for the current viral pandemic, and future ones, needs to be built rapidly.

Despite advances in surgical technique and clinical care, lung transplantation still remains a short-term solution for the treatment of end-stage lung disease. To date, there has been limited experience in experimental lung transplantation using nonhuman primate models. Therefore, we have endeavored to develop a long-term, nonhuman primate model of orthotopic lung transplantation for the ultimate purpose of designing protocols to induce tolerance of lung grafts. Here, we report our initial results in developing this model and our observation that the nonhuman primate lung is particularly prone to rejection. This propensity toward rejection may be a consequence of 1) upregulated nonspecific inflammation, and 2) a larger number of pre-existing alloreactive memory T cells, leading to augmented deleterious immune responses. Our data show that triple-drug immunosuppression mimicking clinical practice is not sufficient to prevent acute rejection in nonhuman primate lung transplantation. The addition of horse-derived anti-thymocyte globulin and a monoclonal antibody to the IL-6 receptor allowed six out of six lung recipients to be free of rejection for over 120 days.

This work presents an approachto predict the low frequency and wave frequency responses (LFR and WFR) of afloating structure using Kalman smoother adaptive filters based time domain Volterramodel. This method utilized time series of a measured wave height as systeminput and surge motion as system output and used to generate the linear andnonlinear transfer function (TFs). Based on those TFs, predictions of surgemotion in terms of LFR and WFR were carried out in certain frequency ranges ofwave heights. The applicability of the proposed method is then applied in ascaled 1:100 model of a semisubmersible prototype.

This paper discusses the significant percentage increase of environmental impact generated in the manufacturing phase as a result of changes in the key material selection during the product design process. The findings in this paper are important for product designers. They need to pay extra attention when choosing plastics or metals when assessing design alternatives that can reduce the environmental impact. Four products were analysed in this case study namely water pump, hot pot, plastic kettle and stainless steel kettle. The environmental impacts of these four products are assessed by Life Cycle Assessment (LCA) and the CML approach from Institute of Environmental Sciences is adopted as the Life Cycle Impact Assessment method.

We studied the effects of indirect allorecognition on the induction and maintenance phases of tolerance in miniature swine cotransplanted with heart and kidney allografts. MHC class I-mismatched heart and kidney grafts were cotransplanted in recipients receiving CyA for 12 days. Recipients were unimmunized or immunized with a set of donor-derived or control third-party MHC class I peptides either 21 days prior to transplantation or over 100 days after transplantation. T-cell proliferation, delayed type hypersensitivity reaction (DTH) and antibody production were assessed. All animals injected with donor MHC class I peptides developed potent indirect alloresponses specific to the immunizing peptides. While untreated recipients developed stable tolerance, all animals preimmunized with donor allopeptides rejected kidney-heart transplants acutely. In contrast, when peptide immunization was delayed until over 100 days after kidney-heart transplantation, no effects were observed on graft function or in vitromeasures of alloimmunity. Donor peptide immunization prevented tolerance when administered to recipients pre transplantation but did not abrogate tolerance when administered to long-term survivors post transplantation. This suggests that the presence of T cells activated via indirect allorecognition represent a barrier to the induction but not the maintenance of tolerance.

The dissociation onset for halogen atom loss was investigated for 2-iodo and 2-chloropropane ions using a newly developed threshold photoelectron photoion coincidence (TPEPICO) technique that suppresses the effects of hot electrons. This study was undertaken in order to resolve current discrepancies concerning these onsets in the literature. The 0 K dissociation thresholds were determined to be 9.818 ± 0.010 and 11.036 ± 0.010 eV for 2-C3H7I and 2-C3H7Cl, respectively. These numbers agree quite well with photoionization and a mass analyzed threshold ionization (MATI) study, but are significantly lower than onsets measured by the much higher resolution pulsed field ionization PEPICO method. The derived C3H7+heat of formation at 298 K is 803.9 ± 1.5 kJ mol−1, and a more precise value for the 298 K 2-iodopropane heat of formation is −40.8 ± 1.3 kJ mol−1. The derived proton affinity of propene is 746.1 kJ mol−1. We have also performed a high-level ab initiocalculation on the 0 K dissociation limit, E0, for C3H7+from C3H7Cl at the CCSD(T)/CBS level of theory with high-level corrections. The theoretical prediction of 11.048–11.061 eV for E0(C3H7+) from C3H7Cl is found to be consistent with the current experimental value.

Proliferation of the androgen-dependent human prostate LNCaP cells was increased by the androgen DHT. Changes in the steady state level of the nm23 and c-myc mRNA in LNCaP cells, with or without 10 nM DHT, showed the nm23 mRNA to change rapidly, beginning to rise after 2 h and reaching its peak by 4 h of DHT treatment. In contrast, increases in the c-myc gene only became apparent after 4 h of treatment. Maximal increase of nm23 mRNA was observed at 10−9M DHT. The basal expression of c-myc and nm23 mRNAs was between 30-70% lower in the LNCaP cells, as compared with the androgen-independent PC-3 and JCA-1 human prostatic human carcinoma cells. Thus nm23 may be classified as a member of the early androgen-responsive genes.

We present here the assignment and simulation of rotational transitions for the H2+(X 2Σg+, v+=0, 2, 9 and 11) vibronic bands using the Buckingham–Orr–Sichel (BOS) model. The simulation shows that perturbation of PFI-PE rotational line intensities due to near-resonance autoionization decreases as v+increases. Experimental rotational constants for H2+(X 2Σg+, v+=0, 2, 9 and 11) are determined with higher accuracy than those obtained in previous HeI and NeI photoelectron studies. In agreement with previous experimental and theoretical investigations, only the ΔN=0 and ±2 rotational branches are observed in the PFI-PE spectrum for H2.

The fate of tryptophan in the isolated perfused rat liver was investigated. It was shown that the liver removed the L-isomer more rapidly from the perfusate than the D-isomer. The 10 g liver was capable of a removal rate of 35 mg/hour when 42 mg of DL-tryptophan was given initially, followed by infusion at the rate of 42 mg/hour. Carbon-14 from DL-tryptophan-2-14C appeared in CO2much more rapidly and to a greater extent within 3 hours than did that from DL-tryptophan-7a-14C. In contrast to whole-animal studies, it was shown that overloading doses of acetoacetate were labeled by DL-tryptophan-5- or 7a-14C. The labeling pattern in acetoacetate was similar to that observed when 14C-fatty acids are the substrate. Acetoacetate overloading suppressed the production of radioactive carbon dioxide from DL-tryptophan-7a-14C.

SL- and DL-allo-5-hydroxylysine-6-14C and L-5-hydroxlysine-3H were administered intraperitoneally to intact rats and the degradative products were trapped by the metabolite overloading technique. Hydroxylysine was readily oxidized; approximately 40% of the 14C was expired as 14CO2in 24 hours. Urinary 5- hydroxypipecolate, α-ketoadipate, glutarate and crotonate were identified as labeled degradation products isolated from the urine. The specific activities of glutamate, aspartate and alanine isolated from the carcass protein were too low to permit the determination of the labeling pattern. This low activity and the rapid release of 14CO2suggests that C(6)of hydroxylysine reaches these amino acids via 14CO2. The degradation of hydroxylysine appears to proceed by reactions parallel to those which degrade lysine with the site of dehydroxylation as yet uncertain.

A mixer linearisation technique based on difference frequency injection has been proposed and experimentally presented in a system level approach. The system analysis and the effects of amplitude and phase sensitivity on its performance are described. The technique has been demonstrated with an L-band up-conversion double-balanced diode mixer and both simulation and experimental results achieved have shown that this technique can substantially reduce third-order intermodulation distortion.

The design of a broadband coplanar waveguide (CPW) Marchand balun fabricated using a photoimageable thick-film process is described. A multilayer coupling structure is employed to obtain a tight coupling. The technique is suitable as a low cost means of fabricating balanced mixers and modulators, with the balun requiring no bond-wires or through-substrate vias. The balun operates from 2 to 9 GHz with an excellent performance.

The design and measurement of a 10 GHz miniaturised branch-line coupler using thick-film photoimageable materials is presented. This attempts to reduce passive component size by demonstrating thin-film microstrip (TFMS)-based structures with a thick film processing technology. This technique offers a cheaper and faster way to implement compact multilayer circuits compared to thin-film technology. The fabricated hybrid of intrinsic area 1.19 × 1.07 mm demonstrates excellent performance and the measurements are in good agreement with the simulations.

In this paper, model calculations were used to predict the external ? dose rate and indoor 222Rn concentration inside a typical dwelling found in Hong Kong. The radionuclide contents in the building materials were taken from previous measurements. The equivalent ? dose rate inside the room built of concrete was computed to be about 0.95 mSv.y-1 which was in good agreement with a previously measured population-weighted mean equivalent ? dose rate of 0.93 mSv.y-1. This value was a few times higher than the reported values in European countries. Addition of fly ash to the concrete has only a slight effect in the ? dose rate. The computed indoor 222Rn concentration also agreed with the arithmetic mean of 42 Bq.m-3 obtained in a previous survey. The seasonal variation of indoor 222Rn concentration was predicted by considering the change in ventilation and meteorological conditions. Based on the predicted values, the excess lung cancer cases attributable to indoor 222Rn was estimated to be 201 and 67 for men and women respectively.