Tube Method Research Articles

Evaluation of Induced Sputum against Gastric Juice Aspirate in the Diagnosis of Tuberculosis in Children: A Cross-sectional Study

Introduction: Diagnosing Tuberculosis (TB) in children is difficult as they do not expectorate sputum on their own, and the sample is usually paucibacillary. Hence, alternative sampling methods like Gastric juice Aspiration (GA), which is the widely accepted method, and Induced Sputum (IS) collection, a more novel approach, are used. The IS method has several advantages, such as being less invasive, not requiring inpatient admission, causing less discomfort, and not necessitating overnight fasting, compared to the GA method. Aim: To evaluate IS against GA for diagnosing TB using XpertMTB/ RIF assay, as well as mycobacterial culture, in children aged between 2 and 15 years. Materials and Methods: This cross-sectional study was conducted in the Department of Paediatrics at Christian Medical College and Hospital, Vellore, Tamil Nadu, India from June 2019 to March 2020, involving 138 children aged between 2 and 15 years who were being evaluated for TB. GA samples were collected after an overnight fast, and on the same day, atleast two hours later, IS samples were collected by trained staff. Both samples underwent mycobacterial smear and culture using the Mycobacteria Growth Indicator Tube (MGIT) method and Xpert MTB/RIF assay. Confirmation of pulmonary TB was based on atleast one of these tests being positive. The ‘Wong-Baker’ Visual Analogue Scale (VAS) was individually administered to each patient to compare the discomfort associated with GA and IS procedures. The differences in yield between IS and GA were tested for significance using the Two-sample test of proportions with a significance level set at 5%. McNemar's χ2 test was employed to compare matched observations. The MannWhitney test was used for comparing continuous variables, and the Chi-Square test for categorical variables. Cohen’s Kappa (κ) was used to assess interobserver agreement between the sampling methods using the different tests. Results: Out of the 138 cases recruited with suspected pulmonary TB, the diagnosis was microbiologically confirmed in 13 cases (9.4%). The overall diagnostic yield was 12/138 (8.7%) for GA and 10/138 (7.2%) for IS. In children under 10 years, GA outperformed IS with all three cases being positive by GA and none by IS. For those aged 10 years and above, 10 children (100%) tested positive with IS, while nine children (90%) were positive with GA. According to the Wong-Baker VAS measuring discomfort during the procedure, IS was favoured over GA (p-value<0.0001). Conclusion: IS performs similarly or better than GA in children over 10 years, while GA performs better than IS in children under 10 years of age. IS is reported to cause less discomfort than GA on the Wong-Baker VAS.

Transformation of Allium sativum Leaf Agglutinin (ASAL) Gene in Cotton through Pollen Tube Method to Enhance Resistance against Whitefly

Transformation of Allium sativum Leaf Agglutinin (ASAL) Gene in Cotton through Pollen Tube Method to Enhance Resistance against Whitefly

PHYSICOCHEMICAL, MICROBIOLOGICAL AND SENSORY EVALUATION OF SHELLED BANANA JUICE

This work aimed to evaluate the physical-chemical, microbiological and sensorial characteristics of unpeeled banana vitamin. The bananas of the cultivar Nanica (Musa acuminata Dwarf Cavendish) were in the 7th stage of maturation. The UHT whole milk used had 3% fat. The treatments were 0%, 10%, 25% and 35% addition of banana peel to the banana smoothie. The physical-chemical analyzes (acidity, pH, density, moisture, ash and fat) were carried out in triplicate, according to the methods of Adolfo Lutz. For microbiological evaluation, the analyzes of total coliforms (35ºC) and thermotolerant coliforms (45ºC) were performed using the multiple tube method and the results expressed in MPN/g. Sensory assessment was applied to 50 untrained panelists using a nine-point structured hedonic scale blind test. Data were subjected to ANOVA and Tukey's test with 5% significance to verify interactions between means. The acidity showed a statistically significant difference, with an average of 1.59%. The mean pH was 6.57 and showed statistical differences between treatments. For density, moisture, fat and ash, the averages were 1,543 g / dm3, 84.17%, 1.03% and 0.83%, respectively. Microbiological analyzes were negative for total coliforms and thermotolerant coliforms, indicating that good manufacturing practices were efficient. For sensory evaluation, the highest acceptance rate was for the treatment of 25% and 54% of the tasters consume banana smoothie at least once a month. The results of the physical-chemical analyzes allow us to infer that the peeled banana smoothie is a low-fat food, thus showing that it can be considered a low-calorie food. Microbiological analyzes showed that the vitamin was produced within good manufacturing practices, as the results for coliforms were negative for all samples. Sensory analysis allowed us to verify that the treatment with the best acceptance rate was the one with 25% of bark, but we will indicate the treatment with 35% of bark, since there was no statistical difference between the formulations in relation to acceptance.
 Keywords: food waste use, low cost food, quality control

Sound-absorbing and thermal insulating properties of natural coir/jute hybrid composites for functional materials

A composite designed for soundproofing integrates both sound absorption materials and thermal insulation, combining the benefits of both into a single product. The absorption component serves to dissipate energy within the system, while the noise barrier reduces the transmission of sound. This study focuses on experimentally assessing the sound absorption coefficients of hybrid composite materials composed of coir and jute fibers, reinforced with epoxy resin, using compression molding techniques. Six different composite samples were prepared with varying blend proportions of these fibers: S1 Coir/100, S2 Jute/100, S3 Coir/Jute 50/50, S4 Coir/Jute 70/30, S5 Coir/Jute 30/70, and S6 Coir/Jute 60/40, following the standards set by the American Society for Testing and Materials (ASTM). The physical and morphological properties of the samples were examined using a Scanning Electron Microscope (SEM), while the sound absorption coefficients (SAC) were measured via the impedance tube method, following ASTM E (1050), and Thermal insulation values were measured according to Lee’s disk method (ASTM C177). The experimental results show the thermal resistance performances of natural fiber composites based on coir/jute fiber materials, is S5 C/J (0.156 W/mK) and S6 C/J (0.146 W/mK), and there is an improvement in thermal conductivity when compared to the rigid polyurethane foam, which is one of the most efficient thermal insulators. Across frequencies ranging from 1600 to 5000 Hz. The results indicated that the composite sample S4 C/J exhibited exceptional performance in absorbing high-frequency sound waves, particularly above 2500 Hz. Furthermore, it was observed that increasing the thickness of the S6 C/J composite could significantly enhance its sound absorption coefficient at medium and low frequencies. These findings underscore the potential of coir and jute fiber-based composites as effective sound-absorbing materials. Notably, these composites exhibit sound absorption coefficients exceeding 0.83%, showcasing their promising acoustic properties. Additionally, the utilization of natural fibers such as coir and jute, sourced from renewable materials, offers advantages of affordability, biodegradability, and recyclability, making them sustainable choices for soundproofing and thermal insulating materials.

Acoustic performance analysis of wooden structure building wall by integrating BIM technology and impedance tube method.

With the increasing demand for building acoustic performance, accurately evaluating the acoustic performance of building walls has become an important research topic. However, existing research has mostly focused on general building materials such as concrete, iron and steel, and glass. For wooden structure wall, due to the sound absorption performance of the materials themselves and the complexity of structural design, the analysis of their acoustic performance is still relatively weak. Moreover, there is a lack of quantitative description of their spectral characteristics and acoustic impedance. To analyze the acoustic performance of wooden structure building walls, Building Information Model (BIM) and impedance tube method were integrated to construct a building wall performance testing system with BIM technology. The impedance tube method was applied and testing functions for sound absorption and insulation performance were designed. The outcomes indicated that in the error test, the error range between the experimental group and the control group was [0.01, 0.18], indicating a high reliability of the experimental results. In the calculation of sound insulation of different specimens at different sound frequencies, when the frequency was 1600Hz, the sound insulation of the control group and experimental group was 65.30dB and 70.14dB, proving the effectiveness of the design method. The above results demonstrate the practicality of integrating BIM technology and impedance tube method in the acoustic performance analysis of wooden structure building walls. This study provides strong technical support for reducing the indoor environment of wooden buildings and improving the comfort of people's living environment.

A comparative study to assess diagnostic efficacy of micro typing gel technique versus conventional tube technique in blood cross-match in blood bank at a tertiary care hospital

Abstract: BACKGROUND: In transfusion medicine, cross-matching and compatibility are determined using the conventional tube approach. The goal of the current study is to compare the microtyping gel approach to the conventional tube method for studying blood cross-match. OBJECTIVES: The objective of the study was to assess the compatibility of donor’s blood with recipient blood by microtyping gel technique and conventional tube technique and comparison of advantages and disadvantages of the two techniques. MATERIALS AND METHODS: This observational, cross-sectional study investigation was carried out in a tertiary care facility’s blood bank for 1½ years. It was decided to compare the effectiveness of the traditional tube and gel techniques. RESULTS: In the current investigation, we evaluated the age of the study participants and found that the majority of the study participants were male (63.17%) and most of them were between the ages of 21 and 40 years. The men-to-women ratio in this study was 1.71:1. About 2300 blood samples were subjected to compatibility testing using both the traditional test tube technology and the microtyping gel technology. The conventional method and the gel card approach are equivalent in terms of sensitivity and specificity. However, the gel card approach is simple to use, quick, reliable, and allows for the recording of data. The spin saline tube approach, in comparison, takes longer and produces unreliable results. This makes the gel card approach preferable to the conventional method. The findings were examined. CONCLUSIONS: Although the conventional tube technology is still regarded as the gold standard for pretransfusion analysis, it nevertheless has several drawbacks and relies on the precise hand–eye coordination of the laboratory staff. We advise using the microtyping gel approach due to its ease of use, stability of outcomes, dispensing of controls and absence of washing process, and equivalent specificity and sensitivity.

Estimation of ABO Anti-A and Anti-B Agglutinin Titers among Blood Donors at a Tertiary Care Referral Teaching Hospital Blood Centre in Southern India: A Cross-sectional Study

Introduction: Transfusion of blood Group O and its components with high ABO antibody titers to non O recipients has been shown to cause acute transfusion reactions, especially in platelet transfusions, as platelets contain significant amounts of ABO antigen on their surface as well as Anti-ABO alloisogglutinins in plasma. Aim: To estimate the ABO Anti-A and Anti-B agglutinin titers among blood donors at a tertiary care referral teaching hospital blood centre. Materials and Methods: This cross-sectional observational study was conducted at the Immunohaematology laboratory of the Department of Transfusion Medicine, Sri Venkateswara Institute of Medical Sciences, Tirupati, Andhra Pradesh, India, from March 2021 to June 2022. All blood donors presenting to the blood centre were screened for eligibility for blood donation. Donors who fulfilled the eligibility criteria as per the Drugs and Cosmetics Act, 1940, and Rules, 1945 were included. Anti-A and Anti-B titers were determined by the conventional tube method with dilutions of 1 in 2, 1 in 4, 1 in 8, 1 in 16, 1 in 32, 1 in 64, 1 in 128, 1 in 256, 1 in 512, and 1 in 1024. A titer of <64 was considered as a low titer, while a titer of >64 was considered as a high titer. Results: A total of 399 donors were included in the study, with 393 (98.5%) being males and 6 (1.5%) being females. The mean age of the study population was 28.49 years. Among blood group A, the percentage of individuals with an IgM anti-B titer of <64 was 85.44% (88) and >64 was 14.56% (15), whereas in blood group B, IgM anti-A titers of <64 were 65.5% (93) and >64 were 34.5% (49). In blood group O, the percentage of individuals with <64 and >64 titers of IgM anti-A were 52.60% (81) and 47.40% (73), respectively, whereas for anti-B, <64 and >64 titers were 77.92% (120) and 22.08% (34), respectively. Conclusion: It is recommended that a database be maintained in all institutes by estimating antibody titers for every A, B, O blood group donors. Whole blood or platelets from group O donors with IgM Anti-A and Anti-B antibody titers <64 can only be transfused across the ABO barrier. As the majority of group A donors had titers <64, group A platelets may be transfused across the ABO barrier in emergency situations.

Assessment of orofacial nociceptive behaviors of mice with the sheltering tube method: Oxaliplatin-induced mechanical and cold allodynia in orofacial regions.

Preclinical studies on pathological pain rely on the von Frey test to examine changes in mechanical thresholds and the acetone spray test to determine alterations in cold sensitivity in rodents. These tests are typically conducted on rodent hindpaws, where animals with pathological pain show reliable nocifensive responses to von Frey filaments and acetone drops applied to the hindpaws. Pathological pain in orofacial regions is also an important clinical problem and has been investigated with rodents. However, performing the von Frey and acetone spray tests in the orofacial region has been challenging, largely due to the high mobility of the head of testing animals. To solve this problem, we implemented a sheltering tube method to assess orofacial nociception in mice. In experiments, mice were sheltered in elevated tubes, where they were well accommodated because the tubes provided safe shelters for mice. Examiners could reliably apply mechanical stimuli with von Frey filament, cold stimuli with acetone spray, and light stimuli with a laser beam to the orofacial regions. We validated this method in Nav1.8-ChR2 mice treated with oxaliplatin that induced peripheral neuropathy. Using the von Frey test, orofacial response frequencies and nociceptive response scores were significantly increased in Nav1.8-ChR2 mice treated with oxaliplatin. In the acetone spray test, the duration of orofacial responses was significantly prolonged in oxaliplatin-treated mice. The response frequencies to laser light stimulation were significantly increased in Nav1.8-ChR2 mice treated with oxaliplatin. Our sheltering tube method allows us to reliably perform the von Frey, acetone spray, and optogenetic tests in orofacial regions to investigate orofacial pain.

Distribution of ABO, RhD Blood Group among Secondary School Students at Bishops Girls Secondary School Rushere Kiruhura Southwestern Uganda

ABO and Rhesus blood group antigens are inherited genetic markers in human blood. Haemoglobin is an efficient transporter of oxygen from the lungs to the tissues and carbon dioxide from tissues to the lungs for exhalation. The study was to determine the distribution of ABO and Rhesus blood groups among secondary school female students. The blood samples of 107 secondary school students at Bishops girls’ Secondary School Rushere kiruhura Southwestern Uganda between July to August, 2023 were collected and their haemoglobin genotypes were determined using HemoTypeSC™ rapid test kit and ABO and Rhesus blood groups were determined by a standard tube method. Results. The frequencies of ABO blood groups among the study population were 20 (18.5%), 24 (22.5%), 06 (5.4%) and 57 (53.6%) for blood group A, B, AB, and O respectively. Also, the distribution of Rhesus (D) positive and Rhesus (D) negative were reported as 98 (91.6%) and 9 (8.4%) each. There was no association between ABO, Rhesus (D) and Hb genotypes observed. Data revealed that Rhesus (D) positive students were statistically higher in number compared to the Rhesus (D) negative students (p=0.000). The sequence of ABO distribution among the rural population in southwestern Uganda is; O > A > B > AB. The frequency of Rhesus (D) negative is very low among secondary school students at Bishops’ Girls Secondary School Rushere Kiruhura Southwestern Uganda Keywords: blood groups, ABO blood group, Rh group, Haemolytic Disease of the Newborn

Utilization of Luffa for Acoustic Panel on Interior Wall, A Technical and Perceptual Approach

Luffa Cylindrica is one of Indonesia’s biodiversity, which provides several benefits, such as for making handycraft, cleaning tool and event for building materials. This study aims to investigate the ability of Luffa as a sound absorber and its visual impression when applied to interior walls. The first stage is testing the damping ability of panels made of Luffa. Several specimens of Luffa acoustic panels were made with PVAc adhesive and then tested to determine their damping ability. From the test results using the impedance tube method (ASTME1050-12), the samples met the soundproof requirements with an absorption coefficient of 0.15 - 0.206 at a frequency of 1600 Hz. The lost sound transmission values obtained are in the range of 40-60 dB. Thus, Luffa can be used as a good sound-absorbing material. The next stage is the development of the visual design of the panel so that it has a certain aesthetic or perceptual value. Three designs were made with variations in shape and color into nine samples applied to a wall of interior space. The semantic differential method assessment found that simple and decorative impressions dominated when the panel was applied to interior walls.

Seroprevalence of Antibodies Against Salmonella Enterica in a Healthy Population

Background: In poor nations like India, enteric fever is a severe health issue. For the purpose of diagnosing enteric fever, the Widal test is frequently utilized. In the Western Region of India, this study attempted to measure the baseline antibody titres for Salmonella typhi and paratyphi A, B in healthy persons.
 Methods: A total of 150 blood samples from healthy persons were taken, and the pattern of antibody titre was determined using the conventional quantitative tube method.
 Results: Among 150 blood samples, 103 had shown significant antibody titres (≥ 1:20). The significant proportion (10.7%) of the individuals had anti-O titre ≥ 1:80. Similarly, 86 had anti-H titres of ≥ 1:20 to S. enteric serotype typhi, 23 had a titre of ≥1:80 and 4 had a titre of ≥1:160 respectively. We found 10% and 1.3% for paratyphi A and B, anti-H titres of ≥ 1:20respectively.
 Conclusion: The study's findings suggest that the Western Development Region of India should modify the threshold values for antibody titres against S. typhi to > 1:80 for both anti-O and anti-H titres.

Evaluation of Antimicrobial Activities of Melaleuca alternifolia (Tea tree) Oil Mouthwash on Candida albicans and Streptococcus mutans: In Vitro Pilot Study

Statement of the problem: Herbal mouthwashes have attracted attention recently due to their antimicrobial and anti-inflammatory effects and fewer side effects than chemical preparations. To choose the most suitable mouthwash component among these herbal preparations, in vivo and, in vitro research should be done, respectively. Objective: The effects of the mouthwashes containing Melaleuca alternifolia (tea tree oil, TTO) on the infectious agents Streptococcus mutans and Candida albicans were evaluated. The results were compared with the effect of chlorhexidine (CHX), the accepted gold standard. Material-Method: A 2% concentration of TTO was prepared, and suspensions of microorganisms Candida albicans and Streptococcus mutans by Mc Farland 0.5 standard were obtained. The macrodilution tube method was used to determine the lowest concentration inhibiting growth, and the disk diffusion method was used to determine the growth inhibition zones. Each method was applied for both TTO and CHX. Results: It was determined that TTO did not inhibit the growth of S. mutans and C.albicans at 2% concentration and MIC value could not be obtained. On the other hand, it was observed that after the treatment with CHX, in C.albicans and,S.mutans samples inhibition zones with the diameters of 10 and 20 mm were formed, respectively. Conclusion: TTO cannot be a successful alternative to CHX for its 2% concentration; It has been concluded that it can increase its antimicrobial effect with different concentrations and other essential oil combinations.

Morphology Profile, Anatomy and Phytochemistry of Beluntas Leaves (Pluchea indica)

Beluntas (Pluchea indica), is one of species in Asteraceae family, traditionally used to increase appetite, to treat indigestion, rheumatism and body odor problems. This study aims to provide morphological and anatomical profiles of Beluntas leaves which are often used in medicine, to determine the chemical content of Beluntas leaves using phytochemical screening tests and thin layer chromatografic profiles, and also to determine flavonoids, polyphenols and alkaloids contents. The observation results showed Beluntas leaves are an oval leaf shape with pinnate leaf reinforcement. Anatomical observation of the leaves, found that the leaf type is equifacial with collateral vascular bundles, the presence of non glandulair multicellular trichomes with constricted in the cross wall, papillae and glandular Compositae trichomes. Tube method results and thin layer chromatography profiles showed Beluntas leaves contained polyphenols, saponins, alkaloids, flavonoids, steroids and essential oils. The chromatogram profile with infrared spectrophotometry shows the wave numbers in the fingerprint region 1515 – 1516, 1259 – 1260, 1159 – 1162, 1112 – 1115, 1046 – 1048, 811 – 812, 505 – 506 and 452 – 454 cm-1. The total amounts of polyphenols, flavonoid and alkaloid contained in Beluntas leaves were 3.1 - 7.7% w/w, 0.5 - 1.2% w/w and 0.03 – 0.08% w/w, respectively.

Frequency of red blood cell allo-immunization in patients undergoing blood transfusion at the Uganda Cancer Institute.

There is limited data on red blood cell (RBC) alloimmunization in patients with cancer in sub-Saharan Africa (SSA). We examined the frequency of RBC alloimmunization in transfused patients with cancers in Uganda. A randomized control trial was conducted on participants at the Uganda Cancer Institute. Eligible participants were age ≥15 years and required blood transfusion. Participants were randomized to receive either leucoreduced or non-leucoreduced blood transfusion. Participants' plasma samples were screened for RBC alloantibodies at enrolment and 3-4 weeks after blood transfusion using a 2-cell panel of reagent group O RBCs using the tube method. Antibody identification was performed using a 10-cell panels of reagent RBCs. Participants were considered alloimmunized if antibodies to RBC antigens were identified. A total of 277 participants were randomized (leucoreduced blood, n=137; non-leucoreduced blood, n=140). Overall, the most represented diagnoses were gynaecological cancers (n=88, 31.8%), acute leukaemia (n=35, 12.6%), and gastrointestinal cancers (n=25, 9.0%). Concomitant HIV infection was present in 26 (9.4%) participants. Most participants received <5 units of blood during the study. No study participant developed allo-antibodies. There was no RBC alloimmunization in participants with cancers. Routine RBC allo-antibody screening in all patients with cancer in SSA requires further research.

Potential Antibacterial Effects of Ethanol Extract and Essential Oil of Origanum vulgare on Klebsiella pneumonia and Staphylococcus aureus

Klebsiella pneumonia (K. pneumonia) and Staphylococcus aureus (S. aureus) are pathogenic bacteria causing various infectious diseases in humans and animals. Currently, herbal ingredients are widely used as antibacterial agents to combat bacterial infections due to their lower side effects, compared to chemical drugs. One such plant with medicinal promise as an antibacterial agent is the oregano plant (Oregano vulgare). It contains substances, such as tannin, flavonoids, carvacrol, thymol, and saponin. Therefore, the current study was conducted to regularly compare the in vitro antibacterial potential of ethanol extract essential oil oregano (Oregano vulgare) on K. pneumonia and S. aureus. In this research, the diffusion method using discs was employed to observe the inhibition zones, while the dilution tube method was utilized to determine the minimum inhibitory concentration (MIC) of the ethanol extract and essential oil of oregano against the test bacteria. The bacterial treatment group received the test material at concentrations of 100%, 50%, 25%, and 12.5%. The obtained data were analyzed descriptively in terms of zone inhibition and MIC values. According to the disc diffusion test, the essential oil of oregano demonstrated greater efficacy as an antibacterial agent against K. pneumoniae at a concentration of 100%, resulting in an average inhibition zone of 18 mm. Conversely, for S. aureus, a concentration of 1.5% of the essential oil exhibited higher effectiveness, yielding an average inhibition zone of 30 mm. Based on the MIC values, the essential oil was more effective as an antibacterial for K. pneumonia at a concentration of 0.2% (2 mg/mL), while for S. aureus it was more effective at a concentration of 0.19% (1.9 mg/mL).

Phytochemical Screening Analysis and Determination of Total Flavonoids and Total Phenolics Content of Ethanol Extract of Sungkai Leaf (Penorema canescens Jack) from Samarinda City

Sungkai is a plant that contains compounds such as flavonoids, tannins, phenolics, saponins, steroids, and terpenoids, which have the potential to develop native Indonesian herbal medicines to treat the prevention and treatment of various diseases. This research aimed to analyze phytochemical screening and the total flavonoid and phenolic content in sungkai leaves originating from Samarinda City. This research method was carried out by extracting sungkai leaves with 96% ethanol and evaporating them with a vacuum rotary evaporator. Sungkai leaf extract was analyzed for phytochemical screening using the tube method with color testing from various reagents and total phenolic and flavonoid content testing using the colorimetric method using a UV-Vis spectrophotometer. The results of the phytochemical screening showed that the ethanol extract of sungkai leaves from Samarinda City was positive for containing flavonoids, saponins, alkaloids, phenolics, and steroids. The results of determining the flavonoid and phenolic content of sungkai leaf ethanol extract were 18,210 ± 0.271 mg QE/g sample and 33,666 ± 1.052 mg GAE/g sample.

Tear Samples for Protein Extraction: Comparative Analysis of Schirmer's Test Strip and Microcapillary Tube Methods.

Tear sampling is an attractive option for collecting biological samples in ophthalmology clinics, as it offers a non-invasive alternative to other invasive techniques. However, there are many tear sampling methods still in consideration. This study explores the suitability of Schirmer's test strip and microcapillary tube as reliable and satisfactory methods for tear sampling. Tear samples were collected from eight healthy volunteers using the standard Schirmer's test strip method with or without anesthesia and microcapillary tubes. The total tear protein concentrations were analyzed via spectrophotometry and bicinchoninic acid (BCA) protein assay. The protein profile was determined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The optimal wetting length of Schirmer's strip and suitable buffer solutions were compared. Discomfort levels reported by participants and the ease of execution for ophthalmologists were also evaluated. Tear samples exhibited typical protein profiles as shown by SDS-PAGE.The mean total protein obtained from an optimum wetting length of 20 mm using Schirmer's strip without anesthesia in phosphate-buffered saline (PBS) yielded substantial quantities of protein as measured by nanophotometer (220.20 ± 67.43 µg) and the BCA protein assay (210.34 ± 59.46 µg). This method collected a significantly higher quantity of protein compared to the microcapillary tube method (p=0.004) which was much more difficult to standardize. The clinician found it harder to utilize microcapillary tubes, while participants experienced higher insecurity and less discomfort with the microcapillary tube method.PBS used during the tear protein extraction process eluted higher tear protein concentration than ammonium bicarbonate, although the difference was not statistically significant. Using anaesthesia did not ease the sampling procedure substantially and protein quantity was maintained. Good quality and quantity of protein from tear samples were extracted with the optimized procedure. Schirmer's strip test in the absence of local anesthesia provided a standard, convenient, and non-invasive method for tear collection.

Reaction between Criegee Intermediate CH2OO and Isobutyraldehyde: Kinetics and Atmospheric Implications

AbstractIn the present work, we have investigated the 1,3‐cycloaddition reaction of isobutyraldehyde ((CH3)2CHCHO) with the simplest Criegee intermediate CH2OO using the OH laser‐induced fluorescence (LIF) method in a reaction tube. The experiments were conducted at temperatures and pressures ranging from 280 to 338 K and 5 to 150 Torr. We found that the bimolecular rate coefficient of the reaction is temperature‐ and pressure‐dependent. The measured rate coefficients at 100 Torr are (4.93±0.89), (4.46±0.80), (3.99±0.72), (3.56±0.64), (3.34±0.60), (2.98±0.54), (2.78±0.50)×10−12 cm3 molecule−1 s−1 at 280, 288, 298, 308, 318, 328, and 338 K, respectively. A high‐pressure limit rate coefficient of (4.47±0.80)×10−12 cm3 molecule−1 s−1 was obtained at 298 K by fitting the pressure‐dependent rate coefficients according to the Lindemann mechanism. The Arrhenius plot of the temperature‐dependent rate coefficients results in an activation energy of (−1.86±0.33) kcal mol−1 and a preexponential factor of (1.72±0.31)×10−13 cm3 molecule−1 s−1. In the atmosphere, the reaction of CH2OO with isobutyraldehyde may contribute to the sink of CH2OO in regions where isobutyraldehyde emission is intense under low temperature and low relative humidity conditions.

Antibiotic Resistance Profile of Biofilm Producing Staphylococci Isolated from Different Clinical Samples

Biofilm mediated infections by Staphylococci have a significant negative impact on patient health and necessitate reliable method for detecting biofilm producers. The ability of isolates to produce biofilm makes them resistant to host immune response as well as available antibiotics. This study aims to detect biofilm producing ability among clinical staphylococci by phenotypic methods and presence of icaAD genes and determine their antibiotic profile. A total of 350 different clinical specimens received in the KIST Medical hospital, Gwarko, Nepal was examined from July 2018 to January 2019 and Staphylococci were identified following standard microbiological procedure. The antibiotic resistivity pattern was detected by Kirby Bauer disc diffusion method whereas biofilm formation was detected by three phenotypic methods viz. congo red agar (CRA), tube method (TM) and tissue culture plate (TCP) method. Furthermore, icaAD genes were detected by PCR method. Chi-square test and independent sample t-test were employed to calculate the significance. A total of 161 Staphylococci were isolated comprising S. aureus (63, 39.1%) and coagulase negative staphylococci (CNS) (98, 60.9%). Most isolates were found to be resistant to penicillin and erythromycin. Strong biofilm formation was detected among 6 (3.7%), 22 (13.7%) and 35 (21.7%) by CRA, TM and TCP method respectively. Similarly, icaAD genes were detected among 24 (14.9%) isolates. Staphylococci isolated from clinical sample showed biofilm forming ability by both phenotypic and genotypic method. The biofilm producing isolates were found to be more resistant to antibiotics than their planktonic counterparts with 56 (89%) and 65 (66%) S. aureus and CNS observed as methicillin resistant respectively. Regular surveillance of biofilm formation by Staphylococci and their antimicrobial resistance profile may lead to early treatment of Staphylococcal infection.

Influence of dwell time on the hydraulic behaviour utilizing multiple injection strategies and a piezoelectric diesel injector

The electric dwell time is defined as the duration between two electric pulse signals. It is a crucial parameter when multiple injection strategies are employed. The influence of electric dwell time on the hydraulic behaviour utilizing pilot injection strategy, split injection strategy, post injection strategy and a commercial piezoelectric diesel injector has been analysed experimentally. To do so, a sweep of electric dwell time from 1.15 ms up to 3 ms in all multiple injection strategies using rail pressures of 80, 100 and 120 MPa, and a back pressure of 5 MPa was performed. A fuel mass of 110 mg was injected in all cases analysed employing operating conditions defined from the characteristics curves of injected mass. The hydraulic behaviour was characterized through to measure the first and second hydraulic delay at opening and closing injector, the pressure oscillations generated during the first injection event, and injected fuel mass during second injection event in an injection discharge curve indicator, which is based on the Bosch tube method. In summary, the paper concludes that the hydraulic dwell time depends on the injected mass during the first injection event, and the dynamic response of injector. Moreover, a short electric dwell time causes an increase of injected fuel mass during second injection event, which can be attributed to combine two effects provoked by overlapping the first and second mass flow rate signals, namely, a reduction in the hydraulic delay at opening injector, and an increase in the hydraulic delay at closing injector. Finally, the present research provides information which can be employed to optimization the modulation of injection rate in a diesel engine.