Quantifying the mitigating effect of organic matter on heavy metal availability in soils with different manure applications: A geochemical modelling study.

Manure is one of the main sources of heavy metal (HM) pollution on farmlands. It has become the focus of global ecological research because of its potential threat to human health and the sustainability of food systems. Soil pH and organic matter are improved by manure and play pivotal roles in determining soil HM behavior. Geochemical modeling has been widely used to assess and predict the behavior of soil HMs; however, there remains a research gap in manure applications. In this study, a geochemical model (LeachXS) coupled with a pH-dependent leaching test with continuously simulations over a broad pH range was used to determine the effects and pollution risks of pig or cattle manure separate application on soil HMs distribution. Both pig and cattle manure applications led to soil pH reduction in alkaline soils and increased organic matter content. Pig manure application resulted in a potential 90.5-156.0 % increase in soil HM content. Cattle manure did not cause significant HM contamination. The leaching trend of soil HMs across treatments exhibited a V-shaped change, with the lowest concentration at pH = 7, gradually increasing toward strong acids and bases. The dissolved organic matter-bound HM content directly increased the HM availability, especially for Cu (up to 8.4 %) after pig manure application. However, more HMs (Cr, Cu, Zn, Ni) were in the particulate organic matter-bound state than in other solid phases (e.g., Fe-Al(hydr) oxides, clay minerals), which inhibited the HMs leaching by more than 19.3 % after cattle manure application. Despite these variations, high HM concentrations introduced by pig manure raised the soil contamination risk, potentially exceeding 40 times at pH ±1. When manure is returned to the field, reducing its HM content and mitigating possible pollution is necessary to realize the healthy and sustainable development of circular agriculture.

Risk factors of preoperative myocardial injury in patients with gastrointestinal tumors.

BACKGROUND: Recent studies indicated that the prognosis of patients with gastrointestinal tumors is frequently influenced by its complications, notably myocardial injury. The main object is to investigate the occurrence and risk factors of myocardial injury in patients with gastrointestinal tumor. METHODS: 1126 patients who received gastrointestinal tumor related surgery from May 2018 to June 2020 in the Sixth Affiliated Hospital of Sun Yat-sen University were retrospectively collected and divided into the non-myocardial injury group and the myocardial injury group (high-sensitive cardiac troponin I (hs-cTnI) ≥ 0.028 ng/ml). The occurrence and risk factors of myocardial injury in patients with gastrointestinal tumor are analyzed. The influence of myocardial injury on the ICU detention time in gastrointestinal tumor patients is also studied. RESULTS: In total, 78 (6.93%) patients developed myocardial injuries. Compared with patients in the non-myocardial injury group, patients in the myocardial injury group have a higher prevalence of cardiovascular risk factors (including advanced age and higher smoking ratio), a higher prevalence of comorbidities (such as previous coronary artery disease, hypertension, atrium fibrillation and diabetes), and a higher rate of premedication (such as anticoagulation, ß-blocker, Angiotensin-converting enzyme inhibitor/Angiotensin II receptor blocker, and diuretic) (all with P-value < 0.05). In addition, patients in the myocardial injury group also presented with a higher revised cardiac risk index (Lee index), higher neutrophil granulocyte ratio, lower hemoglobin, and higher likelihood of impaired cardiac structure and function (all with P-value < 0.05). There was a trend of statistical significance in the ICU detention time between the myocardial injury group and the non-myocardial injury group (1[1,3] vs. 2[1,10], P = 0.064). In this study, there were 7 patients presented with clinical symptoms in the myocardial injury group (chest discomfort in 4 cases, non-compressive precordial chest pain in 1 case, dyspnea in 2 cases). In the multivariate analysis, advanced age, increased Lee index score, increased neutrophil granulocyte ratio, decreased left ventricular ejection fraction (LVEF), increased interventricular septum were independent risk factors for myocardial injury. CONCLUSION: In conclusion, advanced age, increased Lee index, increased neutrophil granulocyte ratio, decreased left ventricular ejection fraction, and increased ventricular septum were independent risk factors for preoperative myocardial injury in patients with gastrointestinal tumors. The proportion of clinical symptoms in gastrointestinal tumor patients with myocardial injury was low, indicating the necessity to closely monitor the cardiac status of individuals with gastrointestinal tumors.

Field performance of sweet sorghum in salt-affected soils in China: A quantitative synthesis.

Sweet sorghum is a high-yield crop with strong resistance, which has the potential to support the development of the forage farming industry in China where vast salt-affected lands are potentially arable. Nutrient management is imperative for sweet sorghum growing on salt-affected lands. Although nitrogen (N) synthetic fertilizers have long been recognized as a key factor for increasing crop yields, their effects on sweet sorghum cultivation are under debate. Consequently, this study integrated the current available observations of yield (n = 255) and partial factor productivity of nitrogen (NPFP, n = 242) of sweet sorghum in salt-affected lands, which included both inland (n = 189) and coastal (n = 66) areas. We quantitatively analyzed the effects of climatic, soil properties and management measures on biomass yield and NPFP of sweet sorghum, comparing the differences between inland and coastal salt-affected lands. We found that average biomass yield and NPFP of sweet sorghum in coastal areas were 19,082.48 ± 8262.75 kg/ha and 107.29 ± 51.44 kg/kg respectively, both significantly lower than that in inland areas (p < 0.05). The N application rate did not have significant promoting effect on the biomass yield of sweet sorghum in inland salt-affected areas (p > 0.05), whereas in coastal salt-affected areas, N application significantly increased the biomass yield of sweet sorghum. Increasing soil organic matter content could promote NPFP in inland areas. The recommended N application rate for inland salt-affected and coastal salt-affected areas were 100 kg/ha and 150 kg/ha respectively. The results indicate that it is crucial to apply nutrient management measures based on the local climatic and soil conditions, since the causes of salinity differ in coastal and inland salt-affected lands. More systematic field studies are required in the future to optimize the management of water and nutrients for sweet sorghum planting in salt-affected lands.

Genetically predicted obstructive sleep apnea is causally associated with an increased risk for periodontitis.

BACKGROUND: Although obstructive sleep apnea (OSA) and periodontitis are associated, whether this association is causative is uncertain. METHODS: We conducted a bidirectional Mendelian randomization (MR) analysis using data from publically accessible genome-wide association studies. The single-nucleotide polymorphisms (SNPs) for OSA were derived from 16,761 cases and 201,194 controls. The pooled data of periodontitis association involved up to 17,353 individuals. Disease-associated single-nucleotide polymorphisms were selected as an instrumental variable at the genome-wide significance level (p < 5.0 × 10- 6). Subsequently, the causal effects were estimated using three different methods: inverse variance weighting (IVW), MR-Egger, and weighted median. Then, these causal estimates were expressed as dominance ratios [odds ratio (OR)]. RESULTS: The MR analysis revealed that genetically determined OSA promotes the development of periodontitis [ IVW OR = 1.117, 95% confidence interval (CI) = 1.001-1.246, p = 0.048). Furthermore, no causal effect of genetically predicted periodontitis on OSA was noted in the reverse MR analysis (IVW OR = 1, 95% CI: 0.95-1.06, p = 0.87). The trend in results from the MR-Egger regression and weighted median (WM) was consistent with that in results from the IVW method. The robustness of the results was confirmed by the sensitivity analysis. CONCLUSIONS: In summary, the results of our MR investigation suggest an association between OSA and periodontitis, proposing that early screening and treatment of OSA is beneficial for the prevention and prognosis of periodontitis.

Joint analytical hierarchy and metaheuristic optimization as a framework to mitigate fertilizer-based pollution.

The emission of nitrogenous pollution from agricultural lands in form of ammonia volatilization, leaching, runoff, N2O emissions, etc. is still a serious challenge to which agricultural sector faces. In this context, a vast number of decision support systems have been developed and tested to find the best nitrogen application rate. These models are highly dependent on crop simulation models, mathematical and regression models, evolutionary algorithms and artificial intelligent, GIS-based models, etc., while in most cases have ignored to be interfered with regional and national regulations established by experts in the field. In this study, a new framework combining analytical hierarchy (AHP)/modified AHP methods (MAHP) plus metaheuristic optimization techniques has been suggested to find the best nitrogen application rate considering regional capacities and requirements. To reach the objectives of the present study a three yield field experiment was conducted upon which crop yield, nitrogen use efficiency, nitrogen uptake, soil nitrate, ammonia volatilization, N2O emissions, and N leaching were monitored or measured. Using the results from the field experiments and a survey from local experts, the models were developed. AHP-assisted optimization model could cause some biases in the final results due to its intrinsic nature which avoids direct pairwise comparison among indicators (so called sub-criteria) under two different main-criteria. On the contrary, MAHP-assisted model could well reflect the concerns of experts and notably decrease hotspot pollution. Such decision support system can satisfy both farmers and environmentalists' need because of the created high profit and low environmental pollution, while saving resources and ensuring a sustainable production system.

Plastic pollution in croplands threatens long-term food security.

Plastic pollution is a global concern given its prevalence in aquatic and terrestrial ecosystems. Studies have been conducted on the distribution and impact of plastic pollution in marine ecosystems, but little is known on terrestrial ecosystems. Plastic mulch has been widely used to increase crop yields worldwide, yet the impact of plastic residues in cropland soils to soil health and crop production in the long term remained unclear. In this paper, using a global meta-analysis, we found that the use of plastic mulch can indeed increase crop yields on average by 25%-42% in the immediate season due to the increase of soil temperature (+8%) and moisture (+17%). However, the unabated accumulation of film residues in the field negatively impacts its physicochemical properties linked to healthy soil and threatens food production in the long term. It has multiple negative impacts on plant growth including crop yield (at the mean rate of -3% for every additional 100 kg/ha of film residue), plant height (-2%) and root weight (-5%), and soil properties including soil water evaporation capacity (-2%), soil water infiltration rate (-8%), soil organic matter (-0.8%) and soil available phosphorus (-5%) based on meta-regression. Using a nationwide field survey of China, the largest user of plastic mulch worldwide, we found that plastic residue accumulation in cropland soils has reached 550,800 tonnes, with an estimated 6%-10% reduction in cotton yield in some polluted sites based on current level of plastic residue content. Immediate actions should be taken to ensure the recovery of plastic film mulch and limit further increase in film residue loading to maintain the sustainability of these croplands.

A 3D Wrist Pulse Signal Acquisition System for Width Information of Pulse Wave.

During pulse signal collection, width information of pulse waves is essential for the diagnosis of disease. However, currently used measuring instruments can only detect the amplitude while can't acquire the width information. This paper proposed a novel wrist pulse signal acquisition system, which could realize simultaneous measurements of the width and amplitude of dynamic pulse waves under different static forces. A tailor-packaged micro-electro-mechanical system (MEMS) sensor array was employed to collect pulse signals, a conditioning circuit was designed to process the signals, and a customized algorithm was developed to compute the width. Experiments were carried out to validate the accuracy of the sensor array and system effectiveness. The results showed the system could acquire not only the amplitude of pulse wave but also the width of it. The system provided more information about pulse waves, which could help doctors make the diagnosis.

Structural Basis for Aza-Glycine Stabilization of Collagen.

Previously, we have demonstrated that replacement of the strictly conserved glycine in collagen with aza-glycine provides a general solution for stabilizing triple helical collagen peptides (Chenoweth, D. M.; et al. J. Am. Chem. Soc. 2016, 138, 9751 ; 2015, 137, 12422 ). The additional hydrogen bond and conformational constraints provided by aza-glycine increases the thermal stability and rate of folding in collagen peptides composed of Pro-Hyp-Gly triplet repeats, allowing for truncation to the smallest self-assembling peptide systems observed to date. Here we show that aza-glycine substitution enhances the stability of an arginine-containing collagen peptide and provide a structural basis for this stabilization with an atomic resolution crystal structure. These results demonstrate that a single nitrogen atom substitution for a glycine alpha-carbon increases the peptide's triple helix melting temperature by 8.6 °C. Furthermore, we provide the first structural basis for stabilization of triple helical collagen peptides containing aza-glycine and we demonstrate that minimal alteration to the peptide backbone conformation occurs with aza-glycine incorporation.

Efficacy and Safety of Statins for Pulmonary Hypertension: A Meta-Analysis of Randomised Controlled Trials.

BACKGROUND: Pulmonary hypertension (PH) is a serious disease, and treatment is a continuing challenge. Some in vitro and in vivo studies identified that statins were effective for PH. However, results of some randomised controlled trials (RCTs) have been controversial. The objective of our study was to clarify whether statins are effective and safe for pulmonary hypertension. METHODS: We systematically searched for eligible RCTs from PubMed, EMBASE, Web of Science, and the Cochrane Library during January 2016. Two reviewers independently extracted data. Standard mean differences (SMDs) and weighted mean differences (WMDs) with 95% confidence intervals (CIs) were estimated for continuous data (exercise capacity cardiac, pulmonary arterial pressure (PAP), cardiac index, and low-density lipoprotein (LDL)). Risk ratios (RRs) were estimated for dichotomous data (adverse events and clinical deterioration). RESULTS: A total of 496 patients from six RCTs were included. Low-density lipoprotein in the statin group decreased significantly compared with the placebo group (WMD = -22.79; 95% CI: -34.33 ∼ -11.24). However, we did not find a statistically significant effect on exercise capacity (SMD = 0.18; 95% CI: -0.34 - 0.71), PAP (WMD = -3.01; 95% CI: -8.68 - 2.65), or CI (WMD = -0.04; 95% CI: -0.15 - 0.23). Additionally, there was no difference between statins and placebo with respect to hepatic injury (RR: 1.12; 95% CI: 0.43 - 2.92), myalgia (RR: 0.81; 95% CI: 0.32 - 2.03), or clinical deterioration (RR: 0.98; 95% CI: 0.58 - 1.67). CONCLUSIONS: Statin treatment appears to be safe but may have no effect on PH.

Efficacy and role of inulin in mitigation of enteric sulfur-containing odor in pigs.

BACKGROUND: The efficacy and role of inulin in the mitigation of enteric sulfur-containing odor gases hydrogen sulfide (H2 S) and methyl mercaptan (CH3 SH) in pigs were examined in this study. Twelve Duroc × Landrace × Yorkshire male finisher pigs (60.7 ± 1.9 kg), housed individually in open-circuit respiration chambers, were randomly assigned to two dietary groups, namely basal diet (control) and basal diet supplemented with 1% (w/w) inulin. At the end of the 45 day experiment, pigs were slaughtered and volatile fatty acid (VFA) concentration, sulfate radical (SO42- ) concentration, population of sulfate-reducing bacteria (SRB) and expression of methionine gamma-lyase (MGL) gene were determined in contents from the caecum, colon (two segments) and rectum. Metabonomic analysis was used to compare differences in biochemical composition, and the Illumina MiSeq procedure to investigate differences in bacterial components, in the different parts of the large intestine between inulin-supplemented and inulin-free (control) groups. RESULTS: Inulin decreased (P < 0.05) the average daily enteric H2 S and CH3 SH production by 12.4 and 12.1% respectively. The concentrations of acetate, propionate and butyrate in the large intestinal content were significantly increased (P < 0.05) with inulin treatment, whereas valerate concentration and MGL mRNA expression decreased (P < 0.05). The growth of Lactobacillus, Butyrivibrio, Pseudobutyrivibrio, Bifidobacterium and Clostridium butyricum was stimulated, while that of Desulfovibrio, the dominant SRB, was inhibited, and there was an accumulation of SO42- in the large intestinal content of the inulin-supplemented pigs, suggesting that inulin mitigates H2 S generation from the SO42- reduction pathway by reducing the growth of SRB. CONCLUSION: The results showed that inulin mitigates CH3 SH generation via three methionine degradation metabolic pathways and H2 S generation from two cysteine degradation metabolic pathways, thus resulting in increased synthesis of these two sulfur-containing amino acids in the pig large intestine. © 2016 Society of Chemical Industry.

General Solution for Stabilizing Triple Helical Collagen.

One of the most ubiquitous stabilizing forces in nature is the hydrogen bond, exemplified by the folded secondary, tertiary, and higher-order structure of biomolecules. Despite the fundamental importance of hydrogen bonding, dependence on this stabilizing force places limitations on nature's proteinogenic building blocks. Herein, we demonstrate that replacement of the strictly conserved glycine in collagen with aza-glycine has profound consequences on the stability and self-assembly of collagen peptides by providing an extra hydrogen bond donor. The additional hydrogen bond provided by aza-glycine allows for complete replacement of glycine residues in collagen peptides and truncation to the smallest self-assembling collagen peptide systems observed to date. Our results highlight the vital importance of hydrogen bonding at desolvated interfaces, providing a new strategy for optimization of designed peptide materials and a general solution for stabilizing the collagen triple helix.

DNA Island Formation on Binary Block Copolymer Vesicles.

Here, we report DNA-induced polymer segregation and DNA island formation in binary block copolymer assemblies. A DNA diblock copolymer of polymethyl acrylate-block-DNA (PMA-b-DNA) and a triblock copolymer of poly(butadiene)-block-poly(ethylene oxide)-block-DNA (PBD-b-PEO-b-DNA) were synthesized, and each was coassembled with a prototypical amphiphilic polymer of poly(butadiene)-block-poly(ethylene oxide) (PBD-b-PEO). The binary self-assembly of PMA-b-DNA and PBD-b-PEO resulted in giant polymersomes with DNA uniformly distributed in the hydrophilic PEO shell. When giant polymersomes were connected through specific DNA interactions, DNA block copolymers migrated to the junction area, forming DNA islands within polymersomes. These results indicate that DNA hybridization can induce effective lateral polymer segregation in mixed polymer assemblies. The polymer segregation and local DNA enrichment have important implications in DNA melting properties, as mixed block copolymer assemblies with low DNA block copolymer contents can still exhibit useful DNA melting properties that are characteristic of DNA nanostructures with high DNA density.

Aza-Glycine Induces Collagen Hyperstability.

Hydrogen bonding is fundamental to life on our planet, and nature utilizes H-bonding in nearly all biomolecular interactions. Often, H-bonding is already maximized in natural biopolymer systems such as nucleic acids, where Watson-Crick H-bonds are fully paired in double-helical structures. Synthetic chemistry allows molecular editing of biopolymers beyond nature's capability. Here we demonstrate that substitution of glycine (Gly) with aza-glycine in collagen may increase the number of interfacial cross-strand H-bonds, leading to hyperstability in the triple-helical form. Gly is the only amino acid that has remained intolerant to substitution in collagen. Our results highlight the vital importance of maximizing H-bonding in higher order biopolymer systems using minimally perturbing alternatives to nature's building blocks.

Endothelial MKK3 is a critical mediator of lethal murine endotoxemia and acute lung injury.

Sepsis is a leading cause of intensive care unit admissions, with high mortality and morbidity. Although outcomes have improved with better supportive care, specific therapies are limited. Endothelial activation and oxidant injury are key events in the pathogenesis of sepsis-induced lung injury. The signaling pathways leading to these events remain poorly defined. We sought to determine the role of MAPK kinase 3 (MKK3), a kinase of the p38 group, in the pathogenesis of sepsis. We used a murine i.p. LPS model of systemic inflammation to mimic sepsis. Lung injury parameters were assessed in lung tissue and bronchoalveolar lavage specimens. Primary lung endothelial cells were cultured and assessed for mediators of inflammation and injury, such as ICAM-1, AP-1, NF-κB, and mitochondrial reactive oxygen species. Our studies demonstrate that MKK3 deficiency confers virtually complete protection against organ injury after i.p. LPS. Specifically, MKK3(-/-) mice were protected against acute lung injury, as assessed by reduced inflammation, mitochondrial reactive oxygen species generation, endothelial injury, and ICAM-1 expression after LPS administration. Our results show that endothelial MKK3 is required for inflammatory cell recruitment to the lungs, mitochondrial oxidant-mediated AP-1, NF-κB activation, and ICAM-1 expression during LPS challenge. Collectively, these studies identify a novel role for MKK3 in lethal LPS responses and provide new therapeutic targets against sepsis and acute lung injury.

A Single Stereodynamic Center Modulates the Rate of Self-Assembly in a Biomolecular System.

Chirality is a property of asymmetry important to both physical and abstract systems. Understanding how molecular systems respond to perturbations in their chiral building blocks can provide insight into diverse areas such as biomolecular self-assembly, protein folding, drug design, materials, and catalysis. Despite the fundamental importance of stereochemical preorganization in nature and designed materials, the ramifications of replacing chiral centers with stereodynamic atomic mimics in the context of biomolecular systems is unknown. Herein, we demonstrate that replacement of a single amino acid stereocenter with a stereodynamic nitrogen atom has profound consequences on the self-assembly of a biomolecular system. Our results provide insight into how the fundamental biopolymers of life would behave if their chiral centers were not configurationally stable, highlighting the vital importance of stereochemistry as a pre-organizing element in biomolecular folding and assembly events.

Prognostic relevance of ventricular arrhythmias in surgical patients with gastrointestinal tumors.

BACKGROUND: Individuals diagnosed with gastrointestinal tumors are at an increased risk of developing cardiovascular diseases. Among which, ventricular arrhythmia is a prevalent clinical concern. This suggests that ventricular arrhythmias may have predictive value in the prognosis of patients with gastrointestinal tumors. AIM: To explore the prognostic value of ventricular arrhythmias in patients with gastrointestinal tumors receiving surgery. METHODS: We retrospectively analyzed data from 130 patients undergoing gastrointestinal tumor resection. These patients were evaluated by a 24-h ambulatory electrocardiogram (ECG) at the Sixth Affiliated Hospital of Sun Yat-sen University from January 2018 to June 2020. Additionally, 41 general healthy age-matched and sex-matched controls were included. Patients were categorized into survival and non-survival groups. The primary endpoint was all-cause mortality, and secondary endpoints included major adverse cardiovascular events (MACEs). RESULTS: Colorectal tumors comprised 90% of cases. Preoperative ambulatory ECG monitoring revealed that among the 130 patients with gastrointestinal tumors, 100 (76.92%) exhibited varying degrees of premature ventricular contractions (PVCs). Ten patients (7.69%) manifested non-sustained ventricular tachycardia (NSVT). The patients with gastrointestinal tumors exhibited higher PVCs compared to the healthy controls on both conventional ECG [27 (21.3) vs 1 (2.5), P = 0.012] and 24-h ambulatory ECG [14 (1.0, 405) vs 1 (0, 6.5), P < 0.001]. Non-survivors had a higher PVC count than survivors [150.50 (7.25, 1690.50) vs 9 (0, 229.25), P = 0.020]. During the follow-up period, 24 patients died and 11 patients experienced MACEs. Univariate analysis linked PVC > 35/24 h to all-cause mortality, and NSVT was associated with MACE. However, neither PVC burden nor NSVT independently predicted outcomes according to multivariate analysis. CONCLUSION: Patients with gastrointestinal tumors exhibited elevated PVCs. PVCs > 35/24 h and NSVT detected by 24-h ambulatory ECG were prognostically significant but were not found to be independent predictors.

Pulse Wave Analysis Method of Cardiovascular Parameters Extraction for Health Monitoring.

OBJECTIVE: A pulse waveform is regarded as an information carrier of the cardiovascular system, which contains multiple interactive cardiovascular parameters reflecting physio-pathological states of bodies. Hence, multiple parameter analysis is increasingly meaningful to date but still cannot be easily achieved one by one due to the complex mapping between waveforms. This paper describes a new analysis method based on waveform recognition aimed for extracting multiple cardiovascular parameters to monitor public health. The objective of this new method is to deduce multiple cardiovascular parameters for a target pulse waveform based on waveform recognition to a most similar reference waveform in a given database or pattern library. METHODS: The first part of the methodology includes building the sub-pattern libraries and training classifier. This provides a trained classifier and the sub-pattern library with reference pulse waveforms and known parameters. The second part is waveform analysis. The target waveform will be classified and output a state category being used to select the corresponding sub-pattern library with the same state. This will reduce subsequent recognition scope and computation costs. The mainstay of this new analysis method is improved dynamic time warping (DTW). This improved DTW and K-Nearest Neighbors (KNN) were applied to recognize the most similar waveform in the pattern library. Hence, cardiovascular parameters can be assigned accordingly from the most similar waveform in the pattern library. RESULTS: Four hundred and thirty eight (438) randomly selected pulse waveforms were tested to verify the effectiveness of this method. The results show that the classification accuracy is 96.35%. Using statistical analysis to compare the target sample waveforms and the recognized reference ones from within the pattern library, most correlation coefficients are beyond 0.99. Each set of cardiovascular parameters was assessed using the Bland-Altman plot. The extracted cardiovascular parameters are in strong agreement with the original verifying the effectiveness of this new approach. CONCLUSION: This new method using waveform recognition shows promising results that can directly extract multiple cardiovascular parameters from waveforms with high accuracy. This new approach is efficient and effective and is very promising for future continuous monitoring of cardiovascular health.

Application of translation wavelet transform with new threshold function in pulse wave signal denoising.

BACKGROUND: The wrist pulse wave under the optimal pulse pressure plays an important role in detecting human body's physiological and pathological information. Wavelet threshold filtering is a common method for pulse wave de-noising. However, traditional filtering methods cannot smoothen the whole pulse wave well and highlight the details. OBJECTIVE: In view of this, an attempt is made in this paper to propose the pulse wave denoising algorithm for pulse wave under optimal pulse pressure according to the translation invariant wavelet transform (TIWT) and the new threshold function. METHODS: Firstly, by using hyperbolic tangent curve and combining the advantages of soft threshold function and hard threshold function, the new threshold function is derived. Secondly, based on the TIWT, pseudo-Gibbs phenomenon gets suppressed. RESULTS: The experiments show that in comparison to the traditional wavelet filtering algorithm, the novel algorithm can better maintain the pulse wave geometric characteristics and has a higher signal to noise ratio (SNR). CONCLUSION: The TIWT with improved new threshold compensates the shortcomings of the traditional wavelet threshold denoising methods in a better way. It lays a foundation for extracting time-domain characteristics of pulse wave.

Myocardial injury before noncardiac surgery.

Non-cardiac surgical procedures present a significant circulatory stress and can potentially trigger cardiovascular events, such as myocardial infarction and heart failure. Myocardial injury before non-cardiac surgery is associated with an increased risk of mortality and major cardiovascular complications during perioperative period, as well as up to 5 years after non-cardiac surgery. While the definition of preoperative myocardial injury is not yet clear, it is generally understood as myocardial injury resulting from various causes of troponin elevation without acute coronary syndrome prior to surgery. Detecting preoperative myocardial injury through routine troponin monitoring is crucial for reducing perioperative risk, but it is also challenging. The aim of this review is to discuss the definition of preoperative myocardial injury, its pathophysiology, implications on clinical practice and decision-making for patients with elevated troponin levels before non-cardiac surgery.