Characteristics of Acoustic Emission Waveforms Induced by Hydraulic Fracturing of Coal under True Triaxial Stress in a Laboratory-Scale Experiment

Hydraulic fracturing (HF) is an effective technology to prevent and control coal dynamic disaster. The process of coal hydraulic fracturing (HF) induces a large number of microseismic/acoustic emission (MS/AE) waveforms. Understanding the characteristic of AE waveforms’ parameters is essential for evaluating the fracturing effect and optimizing the HF strategy in coal formation. In this study, laboratory hydraulic fracturing under true triaxial stress was performed on a cubic coal sample combined with AE monitoring. The injection pressure curve and temporal variation of AE waveforms’ parameters in different stages were analyzed in detail. The experimental results show that the characteristics of the AE waveforms’ parameters well reflect the HF growth behavior in coal. The majority of AE waveforms’ dominant frequency is distributed between 145 and 160 kHz during HF. The sharp decrease of the injection pressure curve and the sharp increase of the AE waveforms’ amplitude show that the fracture already runs through the coal sample during the initial fracture stage. The “trapezoidal” rise pattern of cumulative energy and most AE waveforms with low amplitude may indicate the stage of liquid storage space expansion. The largest proportion of AE waveforms’ energy and higher overall level of AE waveforms’ amplitude occur during the secondary fracture stage, which indicates the most severe degree of coal fracture and complex activity of internal fracture. The phenomenon shows the difference in fracture mechanism between the initial and secondary fracture stage. We propose a window-number index of AE waveforms for better response to hydraulic fracture, which can improve the accuracy of the HF process division.

Evaluation of Salinity by Using Wavelet Modeling

Every year, due to the salinity resulting from improper irrigation practices, almost 10 billion ha of agricultural lands across the world cannot be used. Among the main elements (cations) for salinity in regions with dry or semi-dry climate are potassium (K+), sodium (Na+), calcium (Ca+2) and magnesium (Mg+’2). Using proper irrigation methods as well as ensuring the quality of irrigation water are of great importance in terms of the salinity of agricultural soils. In this study, laboratory analyses of ground water resources for salinity parameters were conducted in the province of Yalova (Taşköprü, Çiftlikköy, and Altınova regions). In the explanation of the analysis results, variations and effects based on the level of salinity were taken into account and the role of small, meso and large scale factors were determined through the use of the wavelet model. The study results would be of use in the estimation of salinity contents of soils with respect to groundwater irrigation in agricultural areas.

Toxicity Evaluation of Selected Plant Water Extracts on a Honey Bee (Apis mellifera L.) Larvae Model

So far, larval rearing in vitro has been an important method in the assessment of bee toxicology, particularly in pesticide risk assessment. However, natural products are increasingly used to control honey bee pathogens or to enhance bee immunity, but their effects on honey bee larvae are mostly unknown. In this study, laboratory studies were conducted to determine the effects of including selected aqueous plant infusions in the diet of honey bee (Apis mellifera L.) larvae in vitro. The toxicity of infusions from three different plant species considered to be medicinal plants was evaluated: tansy (Tanacetum vulgare L.), greater celandine (Chelidonium majus L.), and coriander (Coriandrum sativum L.). The impact of each on the survival of the larvae of honey bees was also evaluated. One-day-old larvae were fed a basal diet consisting of distilled water, sugars (glucose and fructose), yeast extract, and freeze-dried royal jelly or test diets in which distilled water was replaced by plant infusions. The proportion of the diet components was adjusted to the age of the larvae. The larvae were fed twice a day. The experiment lasted seven days. Significant statistical differences in survival rates were found between groups of larvae (exposed or not to the infusions of tansy, greater celandine, and coriander). A significant decrease (p < 0.05) in the survival rate was observed in the group with the addition of a coriander herb infusion compared to the control. These results indicate that plant extracts intended to be used in beekeeping should be tested on all development stages of honey bees.

Comparison of the diagnostic accuracy of monocyte distribution width and procalcitonin in sepsis cases in the emergency department: a prospective cohort study

Background Early diagnosis and treatment of patients with sepsis reduce mortality significantly. In terms of exploring new diagnostic tools of sepsis, monocyte distribution width (MDW), as part of the white blood cell (WBC) differential count, was first reported in 2017. MDW greater than 20 and abnormal WBC count together provided a satisfactory accuracy and was proposed as a novel diagnostic tool of sepsis. This study aimed to compare MDW and procalcitonin (PCT)’s diagnostic accuracy on sepsis in the emergency department. Methods This was a single-center prospective cohort study. Laboratory examinations including complete blood cell and differentiation count (CBC/DC), MDW, PCT were obtained while arriving at the ED. We divided patients into non-infection, infection without systemic inflammatory response syndrome (SIRS), infection with SIRS, and sepsis-3 groups. This study’s primary outcome is the sensitivity and specificity of MDW, PCT, and MDW + WBC in differentiating septic and non-septic patients. In addition, the cut-off value for MDW was established to maximize sensitivity at an optimal level of specificity. Results From May 2019 to September 2020, 402 patients were enrolled for data analysis. Patient number in each group was: non-infection 64 (15.9%), infection without SIRS 82 (20.4%), infection with SIRS 202 (50.2%), sepsis-3 15 (7.6%). The AUC of MDW, PCT, and MDW + WBC to predict infection with SIRS was 0.753, 0.704, and 0.784, respectively (p < 0.01). The sensitivity, specificity, PPV, and NPV of MDW using 20 as the cutoff were 86.4%, 54.2%, 76.4%, and 70%, compared to 32.9%, 88%, 82.5%, and 43.4% using 0.5 ng/mL as the PCT cutoff value. On combing MDW and WBC count, the sensitivity and NPV further increased to 93.4% and 80.3%, respectively. In terms of predicting sepsis-3, the AUC of MDW, PCT, and MDW + WBC was 0.72, 0.73, and 0.70, respectively. MDW, using 20 as cutoff, exhibited sensitivity, specificity, PPV, and NPV of 90.6%, 37.1%, 18.7%, and 96.1%, respectively, compared to 49.1%, 78.6%, 26.8%, and 90.6% when 0.5 ng/mL PCT was used as cutoff. Conclusions In conclusion, MDW is a more sensitive biomarker than PCT in predicting infection-related SIRS and sepsis-3 in the ED. MDW < 20 shows a higher NPV to exclude sepsis-3. Combining MDW and WBC count further improves the accuracy in predicting infection with SIRS but not sepsis-3. Trial registration The study was retrospectively registered to the ClinicalTrial.gov (NCT04322942) on March 26th, 2020.

Evaluating the Effectiveness of Red Onion Skin Extract Derivatives as Oilfield Scale Inhibitors

With growing awareness of the environmental impact of some conventional production chemicals and concerns about the depletion of non-renewable natural resources, increased efforts are being made to use renewable and non-toxic materials in the oilfield. In this study, a potential green scale inhibitor was developed from the skin of red onions and evaluated for calcium sulphate, calcium carbonate and barium scale inhibition. Based on the different extraction processes utilized, two products were obtained and characterized using FTIR and SEM and evaluated using a static jar test procedure. The FTIR results confirmed the bands that make up the major constituents (quercetin) and other important compounds, which supports the present study. Laboratory evaluation show that ROSE can efficiently inhibit calcium sulphate scale and barium sulphate scales with a good inhibition rate of greater than 75% at an optimum dosage. Effect of temperature and dosage on inhibition performance revealed that ROSE is stable at higher temperatures and can effectively inhibit calcium and barium sulphate scales at nearly the same rate without degradation but requires additional dosage to produce same result for calcium carbonate scale. Also, the effect of time reveals that scale inhibitor performs a continuous CaSO4 and CaCO3 inhibition. Not only does ROSE perform excellently in the laboratory condition as a green scale inhibitor, but it also show a relatively close performance rate when compared to an existing commercial inhibitor which indicate that ROSE has a high potential for use in the oil industry.

Application of the Ultrafiltration and Photooxidation Process for the Treatment of Rainwater

As water resources become increasingly scarce, the concept of water reuse is gaining importance. Recently, attention has been paid to the use of rainwater as an alternative water resource. Part of this study, laboratory-scale experiments were conducted to evaluate the effectiveness and efficiency of the ultrafiltration process. The aim of the research was to assess the influence of pollutants from various roof coverings on the ultrafiltration process and the occurrence of membrane fouling. Additionally, the rainwater disinfection process was performed using UV radiation. Analysis of rainwater collected from various roofing materials, evaluating rainwater treatment by ultrafiltration in a cross-flow system, determination of the effectiveness and efficiency of the UF membrane, and additional disinfection of rainwater using UV radiation were carried out. Rainwater was collected from various roofing materials, such as steel roof tiles (RW1), bituminous shingles (RW2), and tar paper roofing (RW3). The treatment efficiency of ultrafiltration was evaluated by monitoring typical quality parameters: color, turbidity, COD, TOC, absorbance of UV254, ammonium, conductivity, and pH. Coliform bacteria, Escherichia coli and Enterococci, were monitored as total number of microorganisms at 22 ± 2 °C after 72 h. As expected, a significant reduction in individual parameters was recorded. COD of rainwater decreased in RW1 by 59%, in RW2 by 69%, and in RW3 by 74%. The ultrafiltration process ensured the complete retention of the coliform bacteria and E. coli. Complete elimination of microorganisms was demonstrated when the ultrafiltration process and UV radiation disinfection were combined.

A Retrospective Study on Laboratory Profile and Clinical Parameters of Dengue Fever Patients

Introduction: Over the past decade, the number of cases of dengue fever has augmented intensely globally. Half the world's population is now under threat. Pakistan has also very high dengue fever per year, with regular reports of dengue outbreaks compared to other countries. Dengue infection should be treated as a solitary ailment with various clinical pictures, vacillating from symptomless situations to severe clinical sequences, which may result in high mortality and morbidity. Aim: To investigate the laboratory parameters and clinical profile in patients with dengue fever. Study Design: A Retrospective observational study. Place and Duration: In the Department of Medicine of Jalan Bani Bu Ali hospital Oman for one-year duration from July 2020 to July 2021. Methods: At least IgM positive or NS1 positive or IgM with NS1 positive or reactive ELISA assay for dengue fever detection but without any co-infection, bone marrow disease confirmed the cases of dengue without other confounding factors, such as alteration of clinical and laboratory data. The results were analyzed for the study. SPSS 21.0 was applied for Statistical analysis. Results: A total of 52 cases were tested positive for dengue fever. The patients mean age was 27.60 +/- 13.98 years and vacillated from 13 to 75 years. Of the total number of patients, 30 (57.69%) were in the age group 21 to 40 years. Of the 52 cases, 36 (69.23%) were male, 16 (30.77%) were female with M:F ratio was 2.2: 1. 42 (80.77%) of all cases were hospitalized for 5 days or less, and 10 (19.23%) were hospitalized for more than 5 days. The mean hospital stay was 3.67±1.40, ranging from 2 to 8 days. Fever was observed in all (100%) of the total number of cases. Conclusions: In this analysis, all patients have fever, and body pain, headache and malaise were communal signs, but a substantial quantity of cases also had respiratory and gastrointestinal symptoms such as nausea, abdominal pain, vomiting, dry cough and diarrhea. Keywords: Dengue fever, clinical profile, retrospective study, laboratory profile, thrombocytopenia

Antioxidant and Antimicrobial Activities of Various Extracts from Safou (Dacryodes edulis) Cultivated in Côte d’Ivoire

Safou (Dacryodes edulis) is a fruit with very interesting nutritional and pharmacological properties. However, this fruit remains rather unknown to the Ivorian population. Aims: The objective of this study was to highlight the antioxidant and antimicrobial potential of the seed and pulp of Safou (Dacryodes edulis) cultivated in Côte d'Ivoire for its valorization. Study Design: Microbiological and biochemical studies Place and Duration of Study: Laboratory of Biotechnology and Food Microbiology,Abidjan, Côte d’Ivoire, between September 2020 and February 2021. Methodology: Aqueous, ethanolic and methanolic extracts of the pulp and seed of Safou were prepared. Moisture content, pH, yield, total polyphenols,diphényl-2-picrylhydrazyle (DPPH) radical scavenging testof the different extracts were determined.Aqueous, ethanolicand methanolicextracts of the seed and pulp at varying concentrations of 200 mg/mL, 100 mg/mL, 50 mg/mL, 25 mg/mL, 12.5mg/mL and 6.25 mg/mL was tested against human pathogens such asEscherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiellapneumoniae, Proteus mirabilis, Aspergillus fumigatus and Penicilliumchrysogenum. Results: pH, moisture content and yield ranged from 3.16 to 4.74; 9 to 18.30%; and 10.79 to 18.78%, respectively. Total polyphenol content ranged from 1.45 mgEAG/g to 4.56 mgEAG/g. The highest levels of total polyphenols were observed for the methanolic extracts of pulp. The different extracts strongly scavenged the DPPH radical with percentages of anti-free radical activity that varied from 50.76 to 64.43%.The antimicrobial susceptibility results of the methanolic extracts of D. edulis seed showed highest zones of inhibition to the microbial isolates tested. The microorganisms were resistant to the aqueous extracts of pulp and seed. Conclusion: The presence of bioactive compounds and the antimicrobial activity of Safou extracts could justify its use in the food and pharmaceutical fields.

Removal of hardness from drinking water by electrocoagulation using iron electrodes

In the present study laboratory studies are carried out to examine the removal of hardness by electrocoagulation process from drinking water using iron rod electrodes in batch mode. The purpose of this study was to investigate the efficiency of EC process in removal of water hardness through iron-rod electrodes in varying conditions. Experimental water sample was taken from water distribution network of local area Pune City, Maharashtra state, India. The indices for calcium and total hardness removal in pH (4.0, 7.0, and 10.0), electrical potential of 12 and 24 V and reaction times of 5 minutes to 30 minutes were measured. The maximum efficiency of hardness removal which was obtained at pH 10.0, voltage of 12 and reaction time of 60 min are equal to 98.5% and 97.5% for calcium and total hardness, respectively. Final pH of remained solution has also increased which rises with acidic pH and decreases in alcoholic pH, so the results demonstrate the direct effect of pH, potential difference and reaction time on hardness removal using EC process.

Herpesvirus Infections of Intestinal Tract in the Patients with Intestinal Graft-Versus-Host Diseases: Laboratory Diagnosis Based on DNA Detection By Real-Time Quantitative PCR in Feces Samples

Background: Intestinal herpesvirus disease remains one of the major causes of morbidity and mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). There is lack of useful methods for etiological diagnosis of intestinal herpesvirus diseases. Here, we evaluated the efficiency of detecting herpesvirus in feces samples via real-time quantitative PCR (RQ-PCR) for diagnosis of intestinal herpesvirus diseases after allo-HSCT. Methods: This was a multicenter, prospective study. Patients with refractory diarrhea after intestinal graft-versus-host diseases (GVHD) were enrolled in this study. Laboratory tests which consisted of morphologic examination, immunohistochemistry, in situ hybridization, and RQ-PCR of tissue homogenate were used to detect viral pathogens including cytomegalovirus (CMV), epstein-Barr virus (EBV), herpes simplex virus (HSV)-I, HSV-II, varicella zoster virus (VZV), adenovirus (ADV) and human herpes virus (HHV)-6, HHV-7. These viruses aforementioned were also detected in feces and blood samples. Results: One hundred and seven patients with refractory diarrhea after intestinal GVHD were enrolled between January 2016 and December 2020. Based on the detection of viruses in biopsy specimens, 75 patients were diagnosed as intestinal infectious diseases including 64 accompanying with intestinal GVHD. CMV was the most frequent pathogen of intestinal infectious diseases (53.8%), followed by EBV (36.5%), bacteria (3.4%) and others (6.3%). For diagnosis of intestinal CMV diseases, the sensitivity and specificity of RQ-PCR in feces samples were better than those of blood (sensitivity: 96.9% v.s. 72.5%, p=0.004; specificity: 93.6% v.s. 75.8%, p=0.035). Similarly, the sensitivity of RQ-PCR in feces and blood samples were 88.2% and 21.9% (p&lt;0.001) and the specificity were 98.5% and 86.3% (p=0.032) for diagnosis of intestinal EBV diseases. Conclusion: Intestinal infectious diseases were one of the main causes of refractory diarrhea after intestinal GVHD. Herpesviruses, especially CMV and EBV, were the most common pathogens. Herpesvirus-DNA detection by RQ-PCR in feces samples was a useful diagnostic method for intestinal herpesviruses diseases. Disclosures No relevant conflicts of interest to declare.