The Value of Lung Injury Score in Assessing the Outcome of Patients with Rib Fracture

Background and Purpose:   

Management of rib fractures constitutes a major part of the trauma workload of any unit. Rib fractures result in disrupted chest wall mechanics and ventilatory insufficiency. The ability of a lung injury scoring system to predict the degree of respiratory dysfunction after rib fractures was evaluated.     

Spontaneous keloids in siblings

The authors report two rare cases of 'non-syndromic spontaneous keloids' occuring in siblings. This represents another unexplored area in the field of 'keloid challenge', warranting further research and development.     

Effect of nitration on protein tyrosine phosphatase and protein phosphatase activity in neuronal cell membranes of newborn piglets

Protein tyrosine phosphatase predominantly determines the status of protein tyrosine kinase-dependent phosphorylation of specific proteins and controls the survival and death of neurons. Previous studies have shown that protein tyrosine phosphatase activity is decreased during hypoxia in cortical membranes of the newborn piglet. We have also shown that nitric oxide (NO) free radicals are generated during hypoxia, and may result in modification of protein tyrosine phosphatase via peroxynitrite-mediated modification. The present study tests the hypothesis that the hypoxia-induced decrease in protein tyrosine phosphatase activity is NO-mediated. To test this hypothesis, in vitro experiments were conducted by measuring protein tyrosine phosphatase activity in the presence of an NO donor, sodium nitroprusside (SNP), or peroxynitrite. Since 3-nitrotyrosine is produced as a consequence of peroxynitrite reactions, we have also examined the effect of 3-nitrotyrosine on protein phophatase activity. Cerebral cortical P(2) membranes were prepared from seven normoxic newborn piglets and each sample was divided into three aliquots: a control group, a SNP group (exposed to 200 microM SNP), and a peroxynitrite group (exposed to 100 microM peroxynitrite). Protein tyrosine phosphatase activity was determined spectrophotometrically in the presence or absence of 2 microM bpV(phen), a highly selective inhibitor of protein tyrosine phosphatase. The protein tyrosine phosphatase activity was 198+/-25 nmol/mg protein/h in the normoxic group, 177+/-30 nmol/mg protein/h in the SNP group (p=NS versus normoxic) and 77+/-20 nmol/mg protein/h in the peroxynitrite group (p<0.001 versus normoxic). The results show that peroxynitrite but not SNP exposure results in decreased protein tyrosine phosphatase activity in vitro. Furthermore 3-nitrotyrosine (100 microm), a product of peroxynitrite, decreased the enzyme activity from 926+/-102 to 200+/-77 (p<0.001). We conclude that protein tyrosine phosphatase regulation is mediated by peroxynitrite. We propose that hypoxia-induced NO production leading to peroxynitrite formation is a potential mechanism of protein tyrosine phosphatase inactivation in vivo. The NO-induced decrease in protein tyrosine phosphatase and protein phosphatase activity, leading to Bcl-2 protein phosphorylation and loss of its antiapoptotic activity may be a NO-mediated mechanism of programmed cell death in the hypoxic brain.     

Prediction of Ecofriendly Concrete Compressive Strength Using Gradient Boosting Regression Tree Combined with GridSearchCV Hyperparameter-Optimization Techniques

A crucial factor in the efficient design of concrete sustainable buildings is the compressive strength (Cs) of eco-friendly concrete. In this work, a hybrid model of Gradient Boosting Regression Tree (GBRT) with grid search cross-validation (GridSearchCV) optimization technique was used to predict the compressive strength, which allowed us to increase the precision of the prediction models. In addition, to build the proposed models, 164 experiments on eco-friendly concrete compressive strength were gathered for previous researches. The dataset included the water/binder ratio (W/B), curing time (age), the recycled aggregate percentage from the total aggregate in the mixture (RA%), ground granulated blast-furnace slag (GGBFS) material percentage from the total binder used in the mixture (GGBFS%), and superplasticizer (kg). The root mean square error (RMSE) and coefficient of determination (R²) between the observed and forecast strengths were used to evaluate the accuracy of the predictive models. The obtained results indicated that—when compared to the default GBRT model—the GridSearchCV approach can capture more hyperparameters for the GBRT prediction model. Furthermore, the robustness and generalization of the GSC-GBRT model produced notable results, with RMSE and R² values (for the testing phase) of 2.3214 and 0.9612, respectively. The outcomes proved that the suggested GSC-GBRT model is advantageous. Additionally, the significance and contribution of the input factors that affect the compressive strength were explained using the Shapley additive explanation (SHAP) approach.     

Multi-Objective Optimization of Process Parameters during Micro-Milling of Nickel-Based Alloy Inconel 718 Using Taguchi-Grey Relation Integrated Approach

This research investigates the machinability of Inconel 718 under conventional machining speeds using three different tool coatings in comparison with uncoated tool during milling operation. Cutting speed, feed rate and depth of cut were selected as variable machining parameters to analyze output responses including surface roughness, burr formation and tool wear. It was found that uncoated and AlTiN coated tools resulted in lower tool wear than nACo and TiSiN coated tools. On the other hand, TiSiN coated tools resulted in highest surface roughness and burr formation. Among the three machining parameters, feed was identified as the most influential parameter affecting burr formation. Grey relational analysis identified the most optimal experimental run with a speed of 14 m/min, feed of 1 μm/tooth, and depth of cut of 70 μm using an AlTiN coated tool. ANOVA of the regression model identified the tool coating parameter as most effective, with a contribution ratio of 41.64%, whereas cutting speed and depth of cut were found to have contribution ratios of 18.82% and 8.10%, respectively. Experimental run at response surface optimized conditions resulted in reduced surface roughness and tool wear by 18% and 20%, respectively.     

Newborn weight change and predictors of underweight in the neonatal period in Guinea‐Bissau,Nepal, Pakistan and Uganda

In low‐ and middle‐income countries (LMIC), growth impairment is common; however, the trajectory of growth over the course of the first month has not been well characterised. To describe newborn growth trajectory and predictors of growth impairment, we assessed growth frequently over the first 30 days among infants born ≥2000 g in Guinea‐Bissau, Nepal, Pakistan and Uganda. In this cohort of 741 infants, the mean birth weight was 3036 ± 424 g. For 721 (98%) infants, weight loss occurred for a median of 2 days (interquartile range, 1–4) following birth until weight nadir was reached 5.9 ± 4.3% below birth weight. At 30 days of age, the mean weight was 3934 ± 592 g. The prevalence of being underweight at 30 days ranged from 5% in Uganda to 31% in Pakistan. Of those underweight at 30 days of age, 56 (59%) had not been low birth weight (LBW), and 48 (50%) had reached weight nadir subsequent to 4 days of age. Male sex (relative risk [RR] 2.73 [1.58, 3.57]), LBW (RR 6.41 [4.67, 8.81]), maternal primiparity (1.74 [1.20, 2.51]) and reaching weight nadir subsequent to 4 days of age (RR 5.03 [3.46, 7.31]) were highly predictive of being underweight at 30 days of age. In this LMIC cohort, country of birth, male sex, LBW and maternal primiparity increased the risk of impaired growth, as did the modifiable factor of delayed initiation of growth. Interventions tailored to infants with modifiable risk factors could reduce the burden of growth impairment in LMIC.     

A-site deficient semiconductor electrolyte Sr1−xCoxFeO3−δ for low-temperature (450–550 °C) solid oxide fuel cells

Fast ionic conduction at low operating temperatures is a key factor for the high electrochemical performance of solid oxide fuel cells (SOFCs). Here an A-site deficient semiconductor electrolyte Sr_1−xCo_xFeO_3−δ is proposed for low-temperature solid oxide fuel cells (LT-SOFCs). A fuel cell with a structure of Ni/NCAL-Sr_0.7Co_0.3FeO_3−δ–NCAL/Ni reached a promising performance of 771 mW cm⁻² at 550 °C. Moreover, appropriate doping of cobalt at the A-site resulted in enhanced charge carrier transportation yielding an ionic conductivity of >0.1 S cm⁻¹ at 550 °C. A high OCV of 1.05 V confirmed that neither short-circuiting nor power loss occurred during the operation of the prepared SOFC device. A modified composition of Sr_0.5Co_0.5FeO_3−δ and Sr_0.3Co_0.7FeO_3−δ also reached good fuel cell performance of 542 and 345 mW cm⁻², respectively. The energy bandgap analysis confirmed optimal cobalt doping into the A-site of the prepared perovskite structure improved the charge transportation effect. Moreover, XPS spectra showed how the Co-doping into the A-site enhanced O-vacancies, which improve the transport of oxide ions. The present work shows that Sr_0.7Co_0.3FeO_3−δ is a promising electrolyte for LT-SOFCs. Its performance can be boosted with Co-doping to tune the energy band structure.

Fast ionic conduction at low operating temperatures is a key factor for the high electrochemical performance of solid oxide fuel cells (SOFCs).     

Impact of productive and dry chronic cough on mortality in the Canadian Longitudinal Study on Aging (CLSA)

BackgroundChronic cough is a common troublesome condition and accounts for a high burden on quality of life. Previous data investigating the mortality associated with chronic cough has been derived in patients with chronic bronchitis. No data exists on chronic dry cough. Therefore, we investigated if chronic dry and productive cough is independently associated with increased mortality.MethodsThe Canadian Longitudinal Study on Ageing (CLSA) is a prospective, nationally generalizable, stratified random sample of adults aged 45–85 years at baseline recruited between 2011–2015 and followed up three years later. Chronic cough was identified based on a self-reported daily cough in the last 12 months. Deaths were confirmed by the Ministry of Health and/or completion of descendent questionnaire by a family member. Models were investigated for dry and productive chronic cough and was adjusted for age, sex, smoking, body mass index (BMI), and respiratory diseases.ResultsOf the 30,016 participants, 4,783 (15.9%) reported chronic cough at baseline; 2,724 (57%) had a dry cough, and 2,059 (43%) had productive chronic cough. There was a total of 561 deaths between baseline and follow-up-1 (3 years later). There was a 49% higher risk of death in participants with chronic productive cough {adjusted odds ratio (aOR) 1.49 [95% confidence intervals (CI): 1.08–2.07]}, but not dry chronic cough [aOR 0.85 (0.60–1.20)]. The effects of chronic productive cough on mortality were persistent in those with no airflow obstruction [chronic productive cough aOR 1.90 (1.09–3.31)].ConclusionsChronic productive cough is associated with a higher risk of death, while chronic dry cough has no impact on mortality risk of death in middle-aged and older adults. This highlights the importance of careful evaluation of patients with chronic cough.