Advances In Instrumentation Research Articles

Biphasic Medium Using Nicotinamide for Detection of Pyrazinamide Resistance in Mycobacterium tuberculosis.

Reliable drug susceptibility testing of pyrazinamide (PZA) is technically difficult, since PZA activity is pH sensitive. The aim of this study was to evaluate a biphasic medium assay (BMA) for the reliable detection of PZA resistance in Mycobacterium tuberculosis (MTB) using nicotinamide (NIC) as a surrogate for PZA and identifying the appropriate cut-off value for the assay. The PZA susceptibility of 122 multidrug-resistant tuberculosis (MDR-TB) isolates and 39 drug-susceptible tuberculosis (DS-TB) isolates was examined using the BMA with NIC at four different concentrations (250, 500, 1000, and 2000 mg/L) and comparing the results with results from the BACTEC MGIT 960 reference method. Out of 122 MDR-TB isolates, 40 were identified as resistant by the BACTEC MGIT 960 system, of which 92.5% contained mutations within their pncA gene plus promoter region. A minimum inhibitory concentration of NIC ≥ 1000 mg/L was used as the cut-off concentration to define resistance in correlation with the MGIT 960 outcomes. NIC-BMA had a sensitivity of 90.91%, a specificity of 100%, and an accuracy of 97.52% compared with the MGIT 960 method. NIC-BMA is a promising assay to screen PZA resistance in microbiological laboratories without automation or advanced molecular instruments.

Determination of Complete Blood Count Reference Values of Mindray BC-760 Hematology Analyzer

Hematological assessment serves as a standard examination in supporting diagnostics in clinical practice. The advanced hematology analyzer instrument namely Mindray BC 760 has recently introduced several new hematological parameters which previously unavailable. This study set out to establish the value of the reference interval of those new parameters on the Mindray BC 760 device in the Indonesian adult population. This observational study took place at Yarsi Hospital, Jakarta from March to August 2023. A total of 352 subjects who underwent medical check-ups at pathology clinics laboratory in the hospital were enrolled. All participants comprised both females and males aged > 17 years and were confirmed to be healthy through examination. Hematological assessment using Mindray BC 760 device. A remarkable significant difference was observed between females and males (p< 0.05) in terms of Hb, RBC, MCH, MCHC, RHE, RET, PLT, PDW, PCT, PLCC, Monocyte and eosinophil count, and neutrophil%. Conversely, MCV, RDW-SD, RET%, IRF, LFR, MFR, HFR, NRBC, NRBC%, WBC, NEU, LYM, BAS, IMG, LYM%, BAS%, IMG%, MPV, IPF showed no significant differences based on gender. It is recommended to adjust of reference interval value according to gender for several novel hematological parameters assessed through the Mindray BC 760 instrument.

Detection of dried jujube from fresh jujube with different variety and maturity after hot air drying based on hyperspectral imaging technology

The consistent quality of dried jujube has a significant impact on its economic value and consumer acceptance. Currently, the evaluation of dried jujube quality heavily relies on agricultural experts and advanced instrument analysis, which is time costly and is limited by many uncertainties. This study aims to develop a rapid and accurate method for classifying dried jujube produced from fresh jujube at different stages of maturity using hyperspectral imaging. Dried jujube samples were collected from two varieties (Zhongyang Muzao jujube and Yuanling jujube) in Hebei Province, representing two maturity stages: Kimri and Rutab. Linear partial least squares-discriminant analysis (PLS-DA), K-Nearest Neighbor (KNN) and support vector machine (SVM)algorithms were combined with six pre-processing methods. the pretreatment spectra of Area Naturalization (AN), Baseline and Multiple scattering correction (MSC) were selected for further analysis. Successive projections algorithm (SPA), Competitive adaptive reweighted sampling （CARS）and Uninformative Variables Elimination (UVE)were combined to select characteristic variables. A total of 16 characteristic variables were selected by AN-UVE-SPA-SVM model. This model achieved the highest accuracies of 96.0 % and 93.1 % in the final discriminant accuracy for the calibration and Validation sets, respectively. The hardness, soluble solid content (SSC), and moisture of two categories of dried jujube derived from fresh jujube at various stages of maturity were analyzed. The results showed that dried jujube produced from fresh jujubes at the Rutab stage were more likely to exhibit characteristics of high SSC and low hardness' compared to those produced at the Kimri stage. The partial least squares regression (PLSR) model established based on characteristic wavelengths extracted by AN-UVE-SPA showed the best results in predicting SSC and moisture. This study showcased the feasibility of identifying and classifying dried jujube using hyperspectral imaging technology, laying a solid foundation for further research in the rapid non-destructive testing of dried fruits and vegetables through the application of hyperspectral technology.

Deep learning bias correction of GEMS tropospheric NO2: A comparative validation of NO2 from GEMS and TROPOMI using Pandora observations

Despite advancements in satellite instruments, such as those in geostationary orbit, biases continue to affect the accuracy of satellite data. This research pioneers the use of a deep convolutional neural network to correct bias in tropospheric column density of NO2 (TCDNO2) from the Geostationary Environment Monitoring Spectrometer (GEMS) during 2021–2023. Initially, we validate GEMS TCDNO2 against Pandora observations and compare its accuracy with measurements from the TROPOspheric Monitoring Instrument (TROPOMI). GEMS displays acceptable accuracy in TCDNO2 measurements, with a correlation coefficient (R) of 0.68, an index of agreement (IOA) of 0.79, and a mean absolute bias (MAB) of 5.73321 × 1015 molecules/cm2, though it is not highly accurate. The evaluation showcases moderate to high accuracy of GEMS TCDNO2 across all Pandora stations, with R values spanning from 0.46 to 0.80. Comparing TCDNO2 from GEMS and TROPOMI at TROPOMI overpass time shows satisfactory performance of GEMS TCDNO2 measurements, achieving R, IOA, and MAB values of 0.71, 0.78, and 6.82182 × 1015 molecules/cm2, respectively. However, these figures are overshadowed by TROPOMI’s superior accuracy, which reports R, IOA, and MAB values of 0.81, 0.89, and 3.26769 × 1015 molecules/cm2, respectively. While GEMS overestimates TCDNO2 by 52 % at TROPOMI overpass time, TROPOMI underestimates it by 9 %. The deep learning bias corrected GEMS TCDNO2 (GEMS-DL) demonstrates a marked enhancement in the accuracy of original GEMS TCDNO2 measurements. The GEMS-DL product improves R from 0.68 to 0.88, IOA from 0.79 to 0.93, MAB from 5.73321 × 1015 to 2.67659 × 1015 molecules/cm2, and reduces MAB percentage (MABP) from 64 % to 30 %. This represents a significant reduction in bias, exceeding 50 %. Although the original GEMS product overestimates TCDNO2 by 28 %, the GEMS-DL product remarkably minimizes this error, underestimating TCDNO2 by a mere 1 %. Spatial cross-validation across Pandora stations shows a significant reduction in MABP, from a range of 45 %-105.6 % in original GEMS data to 24 %-59 % in GEMS-DL.

B2R-Targeting Radiotracer for PET/MR Imaging of Hepatocellular Carcinoma and Guiding Anti-B2R Therapy.

The bradykinin B2 receptor (B2R) is overexpressed in a wide variety of tumors and is a well-defined target for tumor imaging and therapy. The hybrid positron emission tomography/magnetic resonance imaging (PET/MRI) scanner is considered a noninvasive and advanced instrument for precise tumor imaging. In this work, we developed a novel B2R-targeting radiotracer, 68Ga-DOTA-icatibant, for quantifying B2R expression. 68Ga-DOTA-icatibant showed high stability, fast clearance and specific binding to B2R. PET/MR imaging revealed excellent tumor accumulation, and the uptake in tumors could be blocked by DOTA-icatibant. Icatibant-mediated anti-B2R therapy downregulated B2R expression in tumor cells and inhibited the growth of HepG2 tumors, and the decrease in tumor uptake was monitored by timely PET/MR imaging. Hematoxylin and eosin (H&E) and immunohistochemical staining results further demonstrated that the efficacy of anti-B2R could be accurately monitored with the developed PET/MR imaging radiotracer. 68Ga-DOTA-icatibant can be utilized to noninvasively determine B2R expression and dynamically and sensitively monitor the efficacy of anti-B2R therapy.

Instrumental and theoretical advancements in pulsed elution-LC × LC: Investigation of pulse parameters and application to wastewater effluent

Due to the decoupling of the first (1D) and second (2D) dimension in pulsed elution-LC × LC (PE-LC × LC), method development is more flexible and straightforward compared to fast comprehensive LC × LC where the dependencies of key parameters between the two dimensions limits its flexibility. In this study we present a method for pulse generation, which is based on a switching valve alternating between one pump that delivers the gradient and a second pump that delivers low eluotrophic strength for the pause state. Consequently, the dwell volume of the system was circumvented and 7.5, and 3.75 times shorter pulse widths could be generated at flow rates of 0.2, and 0.4 mL/min with satisfactory accuracies between programmed and observed mobile phase composition (relative deviation of 6.0 %). We investigated how key parameters including pulse width and step height, 2D gradient time and flow rate affected the peak capacity in PE-LC × LC. The conditions yielding the highest peak capacity for the PE-LC × LC- high-resolution mass spectrometry (HRMS) system were applied to a wastewater effluent sample. The results were compared to a one dimensional (1D)-LC-HRMS chromatogram. The peak capacity increased with a factor 34 from 112 for the 1D-LC run to 3770 for PE-LC × LC-HRMS after correction for undersampling. The analysis time for PE-LC × LC-HRMS was 12.1 h compared to 67.5 min for the 1D-LC-HRMS run. The purity of the mass spectra improved for PE-LC × LC-HRMS by a factor 2.6 (p-value 3.3 × 10−6) and 2.0 (p-value 2.5 × 10−3) for the low and high collision energy trace compared to the 1D-LC-HRMS analysis. Furthermore, the signal-to-noise ratio (S/N) was 4.2 times higher (range: 0.06–56.7, p-value 3.8 × 10−2) compared to the 1D-LC-HRMS separation based on 42 identified compounds. The improvements in S/N were explained by the lower peak volume obtained in the PE-LC × LC-HRMS.

Ultra-sensitive flexible resistive sensor based on modified PEDOT: PSS inspired by earthworm

Flexible resistive sensors currently face challenges such as low sensitivity and poor stability. In this work, inspired by the skin structure of earthworm, a double strain layer with annular cracks aiming to achieve precise construction of conductive pathways in strain materials is proposed. This design strategy enhances the sensitivity, detection range, stability, and consistency of flexible resistive sensor. The sensing materials utilized primarily consist of mechanically and electrically modified PEDOT:PSS. The sensor showcases high sensitivity (with a gauge factor up to 1973.83), a wide detection range (0 ∼ 10 %), rapid response time (60–70 ms), and exceptional repeatability (1000 cycles). The sensor is integrated into finger clips for measurement of pulse wave. By analyzing features extracted from pulse wave, neural networks are employed for the prediction of encompassing coronary heart disease (CHD), atrial septal defect (ASD), atrial fibrillation (AF) and blood pressure levels. The classification accuracy of CHD, ASD and AF surpasses 96 %. The average prediction errors for systolic blood pressure, diastolic blood pressure and mean arterial pressure are found to be −0.3455, −0.2025 and −0.0319, respectively, meeting the standards set by the Association for the Advancement of Medical Instrumentation and the British Hypertension Society Class A criteria.

NIR-II Surface-Enhanced Raman Scattering Nanoprobes in Biomedicine: Current Impact and Future Directions.

The field of second near-infrared (NIR-II) surface-enhanced Raman scattering (SERS) nanoprobes has made commendable progress in biomedicine. This article reviews recent advances and future development of NIR-II SERS nanoprobes. It introduces the fundamental principles of SERS nanoprobes and highlights key advances in the NIR-II window, including reduced tissue attenuation, deep penetration, maximized allowable exposure, and improved photostability. The discussion of future directions includes the refinement of nanoprobe substrates, emphasizing the tailoring of optical properties of metallic SERS-active nanoprobes, and exploring non-metallic alternatives. The intricacies of designing Raman reporters for the NIR-II resonance and the potential of these reporters to advance the field are also discussed. The integration of artificial intelligence (AI) into nanoprobe design represents a cutting-edge approach to overcome current challenges. This article also examines the emergence of deep Raman techniques for through-tissue SERS detection, toward NIR-II SERS tomography. It acknowledges instrumental advancements like improved charge-coupled devicesensitivity and accelerated imaging speeds. The article concludes by addressing the critical aspects of biosafety, ease of functionalization, compatibility, and the path to clinical translation. With a comprehensive overview of current achievements and future prospects, this review aims to illuminate the path for NIR-II SERS nanoprobes to innovate diagnostic and therapeutic approaches in biomedicine.

Structural Evolution of the Pharmaceutical Peptide Octreotide upon Controlled Relative Humidity and Temperature Variation

Octreotide is the first synthetic peptide hormone, consisting of eight amino acids, that mimics the activity of somatostatin, a natural hormone in the body. During the past decades, advanced instrumentation and crystallographic software have established X-Ray Powder Diffraction (XRPD) as a valuable tool for extracting structural information from biological macromolecules. The latter was demonstrated by the successful structural determination of octreotide at a remarkably high d-spacing resolution (1.87 Å) (PDB code: 6vc1). This study focuses on the response of octreotide to different humidity levels and temperatures, with a particular focus on the stability of the polycrystalline sample. XRPD measurements were accomplished employing an Anton Paar MHC-trans humidity-temperature chamber installed within a laboratory X’Pert Pro diffractometer (Malvern Panalytical). The chamber is employed to control and maintain precise humidity and temperature levels of samples during XRPD data collection. Pawley analysis of the collected data sets revealed that the octreotide polycrystalline sample is remarkably stable, and no structural transitions were observed. The compound retains its orthorhombic symmetry (space group: P212121, a = 18.57744(4) Å, b = 30.17338(6) Å, c = 39.70590(9) Å, d ~ 2.35 Å). However, a characteristic structural evolution in terms of lattice parameters and volume of the unit cell is reported mainly upon controlled relative humidity variation. In addition, an improvement in the signal-to-noise ratio in the XRPD data under a cycle of dehydration/rehydration is reported. These results underline the importance of considering the impact of environmental factors, such as humidity and temperature, in the context of structure-based drug design, thereby contributing to the development of more effective and stable pharmaceutical products.

Increasing Proteome Coverage Through a Reduction in Analyte Complexity in Single-Cell Equivalent Samples.

The advancement of sophisticated instrumentation in mass spectrometry has catalyzed an in-depth exploration of complex proteomes. This exploration necessitates a nuanced balance in experimental design, particularly between quantitative precision and the enumeration of analytes detected. In bottom-up proteomics, a key challenge is that oversampling of abundant proteins can adversely affect the identification of a diverse array of unique proteins. This issue is especially pronounced in samples with limited analytes, such as small tissue biopsies or single-cell samples. Methods such as depletion and fractionation are suboptimal to reduce oversampling in single cell samples, and other improvements on LC and mass spectrometry technologies and methods have been developed to address the trade-off between precision and enumeration. We demonstrate that by using a monosubstrate protease for proteomic analysis of single-cell equivalent digest samples, an improvement in quantitative accuracy can be achieved, while maintaining high proteome coverage established by trypsin. This improvement is particularly vital for the field of single-cell proteomics, where single-cell samples with limited number of protein copies, especially in the context of low-abundance proteins, can benefit from considering analyte complexity. Considerations about analyte complexity, alongside chromatographic complexity, integration with data acquisition methods, and other factors such as those involving enzyme kinetics, will be crucial in the design of future single-cell workflows.

Innovative and Cost-Effective Fabrication Technique for Dielectric Composite Material

In this paper, the fabrication process of epoxy resin and nanocomposite barium titanate using a cost-effective apparatus is presented along with measurements of complex permittivity. The material is prepared by mixing epoxy resin and barium titanate powder which has high permittivity. Measurement of complex permittivity of materials is performed using a waveguide technique in the G-band with a frequency between 4 and 6 GHz. The results are then compared with the previous works that use advanced and precision instrumentation. The results indicate that the material’s permittivity, determined using our proposed technique, performs admirably. Specifically, at a frequency of 5 GHz, the permittivity is 7.32 with a loss tangent of 0.025 for a filler concentration of 20%. These values not only meet but also closely match those obtained with high-end equipment. Therefore, the proposed technique could be a good potential as an alternative technique for dielectric material preparation which is suitable to be used as a substrate antenna.

Stable Isotope Tracing Analysis in Cancer Research: Advancements and Challenges in Identifying Dysregulated Cancer Metabolism and Treatment Strategies.

Metabolic reprogramming is a hallmark of cancer, driving the development of therapies targeting cancer metabolism. Stable isotope tracing has emerged as a widely adopted tool for monitoring cancer metabolism both in vitro and in vivo. Advances in instrumentation and the development of new tracers, metabolite databases, and data analysis tools have expanded the scope of cancer metabolism studies across these scales. In this review, we explore the latest advancements in metabolic analysis, spanning from experimental design in stable isotope-labeling metabolomics to sophisticated data analysis techniques. We highlight successful applications in cancer research, particularly focusing on ongoing clinical trials utilizing stable isotope tracing to characterize disease progression, treatment responses, and potential mechanisms of resistance to anticancer therapies. Furthermore, we outline key challenges and discuss potential strategies to address them, aiming to enhance our understanding of the biochemical basis of cancer metabolism.

Nanoparticulated Bimodal Contrast Agent for Ultra-High-Field Magnetic Resonance Imaging and Spectral X-ray Computed Tomography.

Bimodal medical imaging based on magnetic resonance imaging (MRI) and computed tomography (CT) is a well-known strategy to increase the diagnostic accuracy. The most recent advances in MRI and CT instrumentation are related to the use of ultra-high magnetic fields (UHF-MRI) and different working voltages (spectral CT), respectively. Such advances require the parallel development of bimodal contrast agents (CAs) that are efficient under new instrumental conditions. In this work, we have synthesized, through a precipitation reaction from a glycerol solution of the precursors, uniform barium dysprosium fluoride nanospheres with a cubic fluorite structure, whose size was found to depend on the Ba/(Ba + Dy) ratio of the starting solution. Moreover, irrespective of the starting Ba/(Ba + Dy) ratio, the experimental Ba/(Ba + Dy) values were always lower than those used in the starting solutions. This result was assigned to lower precipitation kinetics of barium fluoride compared to dysprosium fluoride, as inferred from the detailed analysis of the effect of reaction time on the chemical composition of the precipitates. A sample composed of 34 nm nanospheres with a Ba0.51Dy0.49F2.49 stoichiometry showed a transversal relaxivity (r2) value of 147.11 mM-1·s-1 at 9.4 T and gave a high negative contrast in the phantom image. Likewise, it produced high X-ray attenuation in a large range of working voltages (from 80 to 140 kVp), which can be attributed to the presence of different K-edge values and high Z elements (Ba and Dy) in the nanospheres. Finally, these nanospheres showed negligible cytotoxicity for different biocompatibility tests. Taken together, these results show that the reported nanoparticles are excellent candidates for UHF-MRI/spectral CT bimodal imaging CAs.

Comparison of endoscopic third ventriculostomy versus cerebrospinal fluid shunt procedures for the treatment of pediatric hydrocephalus in Taiwan.

Pediatric hydrocephalus is the most common cause of surgically treatable neurological disease in children. Controversies exist whether endoscopic third ventriculostomy (ETV) or cerebrospinal fluid (CSF) shunt placement is the most appropriate treatment for pediatric hydrocephalus. This study aimed to compare the risk of re-operation and death between the two procedures. We performed a retrospective population-based cohort study and included patients younger than 20-years-old who underwent CSF shunt or ETV for hydrocephalus from the Taiwan National Health Insurance Research Database. A total of 3,555 pediatric patients from 2004 to 2017 were selected, including 2,340 (65.8%) patients that received CSF shunt placement and 1215 (34.2%) patients that underwent ETV. The incidence of all-cause death was 3.31 per 100 person-year for CSF shunt group and 2.52 per 100 person-year for ETV group, with an adjusted hazard ratio (HR) of 0.79 (95% confidence interval [CI] = 0.66-0.94, p = 0.009). The cumulative incidence competing risk for reoperation was 31.2% forthe CSF shunt group and 26.4% forthe ETV group, with an adjusted subdistribution HR of 0.82 (95% CI = 0.70-0.96, p = 0.015). Subgroup analysis showed that ETV was beneficial for hydrocephalus coexisting with brain or spinal tumor, central nervous system infection, and intracranial hemorrhage. Our data indicates ETV is a betteroperative procedure for pediatric hydrocephalus when advanced surgical techniques and instruments are available.

LECOM (Lead Extraction COMplexity): a new scoring system for prediction of a difficult procedure

Abstract Background Transvenous lead extraction (TLE) can become far more complex when unanticipated difficulties arise. Aim The aim of this study was to develop a simple scoring system that allows prediction of difficulty and complexity of this important procedure. Methods Based on a retrospective analysis of 3741 extraction procedures (extended fluoroscopy time, need for second-line instruments, and advanced techniques and instruments), a 5-point Complex Indicator of Difficulty of T(LE) Procedure (CID-TLEP) scale was developed. Two or more points on the CID-TLEP scale indicated a higher level of procedure complexity. Results Multivariate regression analysis showed that patient age below 51 years at first CIED implantation, number of abandoned leads, number of previous CIED-related procedures, passive fixation leads to be extracted, multiple leads to be extracted, and a ratio of dwell time of oldest extracted lead to patient age during TLE of >0.13 are significant predictors of higher levels of lead extraction complexity. The ROC analysis demonstrated that the total number of points (the sum of the odds ratios of the above variables) of >9.697 indicated a 21.83% higher probability of complex TLE (sensitivity 74.08%, specificity 74.46%). Finally, the logistic function model was employed, and a simple equation for Lead Extraction COMplexity was constructed to predict the probability of a difficult procedure. The risk of complex extraction (in percentage) was calculated as [1/(1 + 55.34·0.754X)]·100 (P < 0.001). Conclusion (1) The LECOM score can effectively predict the risk of a difficult transvenous lead extraction procedure, and (2) Predicting the probability of a more complex procedure may help clinicians in planning lead removal and improving patient management. (3) Simple on-line calculator should be available to predict a difficulty of planned TLE procedure and to allow to send more demanding patient to more experienced high-volume centre.

Study of Highly Efficient Au/Pt Nanoparticles for Rapid Screening of Clostridium difficile.

This study synthesized core/shell gold-platinum nanoparticles and characterized their colorimetric properties; ultraviolet-visible spectroscopy revealed that the synthesized nanoparticles exhibited distinct colors from conventional gold nanoparticles. Furthermore, the nanoparticles were subjected to lateral flow assays using Protein A, and the results revealed that they outperformed conventional spherical gold nanoparticles in terms of color development. This improvement can be attributed to the distinct core/shell structures of our nanoparticles. Further evaluation revealed that these nanoparticles could facilitate the detection of Clostridium difficile Toxin B visually at an extremely low concentration (1 ng/mL) without the requirement for advanced instrumentation. This substantial improvement in sensitivity can be attributed to the meticulous design and nanoscale engineering of the structure of the nanoparticles.

Promises and Challenges of populational Proteomics in Health and Disease

Advances in proteomic assay technologies have significantly increased coverage and throughput, enabling recent increases in the number of large-scale population-based proteomic studies of human plasma and serum. Improvements in multiplexed protein assays have facilitated the quantification of thousands of proteins over a large dynamic range, a key requirement for detecting the lowest-ranging, and potentially the most disease-relevant, blood-circulating proteins. In this perspective, we examine how populational proteomic datasets in conjunction with other concurrent omic measures can be leveraged to better understand the genomic and non-genomic correlates of the soluble proteome, constructing biomarker panels for disease prediction, among others. Mass spectrometry workflows are discussed as they are becoming increasingly competitive with affinity-based array platforms in terms of speed, cost, and proteome coverage due to advances in both instrumentation and workflows. Despite much success, there remain considerable challenges such as orthogonal validation and absolute quantification. We also highlight emergent challenges associated with study design, analytical considerations, and data integration as population-scale studies are run in batches and may involve longitudinal samples collated over many years. Lastly, we take a look at the future of what the nascent next-generation proteomic technologies might provide to the analysis of large sets of blood samples, as well as the difficulties in designing large-scale studies that will likely require participation from multiple and complex funding sources and where data sharing, study designs, and financing must be solved.

Various tomato infection discrimination using spectroscopy

Diagnosing plant diseases is a difficult task, but it could be made easier with the use of advanced instrumentation and the latest machine learning techniques. This paper is a further development of a previous authors study by the authors, which has been extended to provide the classification method for tomato diseases and to indicate the spectral ranges of greatest importance for this process. As tomatoes are one of the most popular and consumed vegetables, and diseases of this crop even reduce yields by up to 80% every year, their detection is a vague topic. This manuscript describes research in which spectroscopy was used to develop methods for discriminating between selected tomato diseases. The following, frequently occurring diseases were investigated for this research: anthracnose, bacterial speck, early blight, late blight, and Septoria Leaf Spot. The study used a dataset consisting of 3877 measurements taken with the ASD FieldSpec 4 Hi-Res spectroradiometer in the 350–2500 nm range from 2019/09/10 to 2019/12/20. The highest classification efficiency (F1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$F_1$$\\end{document} score) of 0.896 was obtained for the logistic regression based model which was evaluated on Septoria Leaf Spot disease records.

Productivity of operating room from viewpoint operating room nurses in Iran: A national cross-sectional study

BackgroundProductivity refers to the maximum use of human resources in service provision. Due to the existence of advanced equipment and instruments for surgery, the operating room is one of the most complex and income-generating sections of a hospital. Since the improvement of operating room nurses’ productivity can lead to enhanced hospital productivity, this study was done to determine the productivity rate of operating room nurses in Iran. MethodsThis cross-sectional study was done on 533 operating room nurses from 8 metropolises in Iran in 2022. The sampling method in this research was multistage. The data collection instruments were Hersy & Belanchard & Gold.Smith productivity questionnaire and demographic characteristics. After receiving the ethics code, data collection was done for three months. Descriptive and inferential analyses, including independent t-tests and analysis of variance, were used for data analysis. The collected data were analyzed by SPSS 18. P-value < 0.05 was considered statistically significant. ResultsThe mean age of the participants was 29.83 ± 5.94 and 421 of the participants were women. The mean and SD for total productivity in operating room nurses was obtained at 60.83 ± 12.78, below average. Data analysis shows that total productivity was significantly associated with marital status (P-value = 0.035) and working experience (P-value = 0.019). ConclusionConsidering the low mean productivity rate of operating room nurses, researchers recommend that hospital managers pay more attention to the productivity of operating room nurses by knowing the influential factors and implementing proper and high-quality management.

THE CONTRIBUTION OF THE DE FILIPPI EXPEDITION (1913–1914) TO THE GEOLOGICAL KNOWLEDGE OF THE AKSAI CHIN REGION (WESTERN HIMALAYA)

ABSTRACT Between the years 1913 to 1914 the De Filippi Expedition, led by the Italian explorer and mountaineer Filippo De Filippi (1869–1938), traversed the Himalayan Range from Kashmir to Baltistan and Xinjiang. Exploring mostly unknown territories, traveling more than 2000 kilometers, and equipped with advanced instruments for geodetic and meteorological measurements, the expedition members surveyed, mapped and collected rocks and fossils including from the remote Aksai Chin region. After almost two years, the expedition returned to Italy, however, publication of the findings was delayed due to the outbreak of the First World War. The fossil material and syntheses of the geology and stratigraphy of the area represented unique documents on this sector of Western Tibet, with the Cretaceous Period being documented by the expedition for the first time in the whole Trans-Himalayan Range. The Aksai Chin region remains poorly explored even today, and the De Filippi collection which is housed in the Natural History Museum of the University of Florence now represents one of the few records available for reconstructing the stratigraphy of the area. It constitutes a valuable resource regarding the history of the scientific exploration and understanding of the geology and paleontology of the region, providing a unique window into a very remote and fascinating part of the world.