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1.
RSC Adv ; 14(29): 20561-20571, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38946767

ABSTRACT

A new eco-friendly method for creating an optical sensor membrane specifically designed to detect yttrium ions (Y3+) has been developed. The proposed sensor membrane is fabricated by integrating 4-(2-arsonophenylazo) salicylic acid (APASA), sodium tetraphenylborate (Na-TPB), and tri-n-octyl phosphine oxide (TOPO) into a plasticized poly(vinyl chloride) matrix with dimethyl sebacate (DMS) as the plasticizer. In this sensor membrane, APASA functions dually as an ionophore and a chromoionophore, while TOPO enhances the complexation of Y3+ ions with APASA. The composition of the sensor membrane has been meticulously optimized to achieve peak performance. The current membrane exhibits a linear dynamic range for Y3+ ions from 8.0 × 10-9 to 2.3 × 10-5 M, with detection and quantification limits of 2.3 × 10-9 and 7.7 × 10-9 M, respectively. No interference from other potentially interfering cations and anions was observed in the determination of Y3+. The membrane showed strong stability and a swift response time of about 3.0 minutes, with no signs of APASA leaching. This sensor is highly selective for Y3+ ions and can be renewed by treating it with 0.15 M HNO3. It has been effectively applied to measure Y3+ in nickel-based alloys, as well as in biological and environmental samples.

2.
RSC Adv ; 14(27): 19428-19445, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38887646

ABSTRACT

This work illustrated the synthesis of a new simple resorcinol derivative, 4,6-dimethoxyisophthalohydrazide (DMIH) and confirmed its structure using 1H-NMR spectroscopy. The inhibiting performance of the DMIH compound in resisting the pitting action of a 0.5 mol L-1 HCl solution on low-carbon steel (LCS) was assessed. The newly synthesized compound had a simple structure and was dissolved in acidic media. The efficiency of the inhibitor was examined using chemical and electrochemical methods. The DMIH compound significantly decreased the rate of dissolution of LCS in HCl solution by adsorption. The adsorption was based on the Langmuir model. The DMIH compound is adsorbed on LCS via both chemisorption and physisorption. The DMIH compound is a mixed-type inhibitor. An inhibition efficiency (IE) of 83.8% was obtained using 300 ppm of the DMIH compound at 298 K. The IE decreased to 72% as the temperature increased to 328 K. When the concentration of DMIH increased from 50 to 300 ppm, the charge transfer resistance (R ct) increased from 134.7 to 404.8 ohm cm2, and the capacitance of the adsorbed layer decreased from 38 × 10-6 to 11 × 10-6 F cm-2. The high IE of the synthesized inhibitor was validated by the quantum characteristics. Monte Carlo (MC) simulations revealed that the DMIH compound adsorbed to the LCS quite well. The presence of a protective film on the LCS specimen was verified by the scanning electron microscopy (SEM) and atomic force microscopy (AFM) results. DMIH has significant potential to function as a corrosion inhibitor, as indicated by the comparative study between its performance and that of previously reported compounds. Although the structure of the DMIH compound is simpler than that of other inhibitors, it has been proven to be more effective.

3.
Cureus ; 16(5): e61118, 2024 May.
Article in English | MEDLINE | ID: mdl-38919250

ABSTRACT

Background Irritable bowel syndrome (IBS) is a functional gastrointestinal chronic disorder associated with symptoms such as abdominal pain, diarrhea, and constipation. One of the factors that could affect the pathogenesis of IBS is depression, a common psychological disorder that causes social and physical disability and affects productivity. A number of Saudi teachers were found to have depression, which was linked with multiple risk factors including chronic illnesses. However, there is limited data that exhibits the association between IBS and depression, specifically. Therefore, our study aims to determine the impact of depression on IBS-associated gastrointestinal symptoms in Makkah City schools, Saudi Arabia. Methods In this cross-sectional study, we used two validated scales and translated them into Arabic and then we distributed them to our targeted population. Our sample size was determined to be 383 but we succeeded in recruiting 477 participants in our study. Data were statistically analyzed using the statistical software Statistical Package for Social Sciences (SPSS), version 23.0 (IBM Corp., Armonk, NY). Results Generally, participants who demonstrated mild levels of Patient Health Questionnaire-9 (PHQ-9) depression scale corresponded significantly with minimal/mild and moderate levels of Gastrointestinal Symptom Rating Scale-IBS (GSRS-IBS) scores (n = 85 and 76, respectively; p ˂ 0.001), while participants who scored moderately on the PHQ-9 depression scale corresponded significantly with a severe level of GSRS-IBS scores (n = 29; p ˂ 0.001). Conclusion Our study found a significant association between different levels of depression and IBS among participants with a positive history of IBS. Further studies about the prevalence of IBS, depression, and the nature of their relationship are strongly recommended, in addition to the necessity of a suicide risk assessment for those with severe depression.

4.
Vet World ; 17(5): 1168-1176, 2024 May.
Article in English | MEDLINE | ID: mdl-38911073

ABSTRACT

Background and Aim: Klebsiella pneumoniae is one of the most common causes of clinical and asymptomatic mastitis in dairy cattle, as well as in milk and dairy products that affect milk quality. Mastitis caused by K. pneumoniae is even more serious due to its poor response to antibiotic therapy. The aim of this study was to detect and identify the presence of K. pneumoniae in milk and dairy products produced in Libya. Materials and Methods: A total of 234 samples were randomly collected from various locations in Libya. Samples were examined for the presence of K. pneumoniae using conventional cultural techniques, including cultivation in violet red bile agar plus 4-methylumbelliferyl-ß-D-glucuronide broth and CHROM agar, followed by polymerase chain reaction identification and partial sequencing of 16S rRNA. Results: Of the 234 samples of milk and dairy products collected, 16 (6.8%) isolates revealed mucoid colonies on agar media that were phenotypically suggested to be K. pneumoniae. Identification of isolates was confirmed using molecular techniques (16S rRNA). Among the examined samples, K. pneumoniae was recovered from camel's milk, raw cow's milk, raw fermented milk, Maasora cheese, Ricotta cheese, soft cheese, full cream milk powder, milk powder infant formula, cereal baby food, and growing-up formula. Antibiotic susceptibility testing was performed on 12 of the 16 K. pneumoniae isolates, and the results showed that K. pneumoniae isolates were resistant to more than eight antibiotics; interestingly, two isolates showed metallo-beta-lactamase (MBL) production. Conclusion: K. pneumoniae is considered a risk to human health because many of these products do not comply with the microbiological criteria of international and/or Libyan standards. This study emphasized the relationship between K. pneumoniae and raw milk, cheese, milk powder, and infant milk retailed in Libya. There is a need to take the necessary measures to ensure effective hygiene practices during production in dairy factories, handling, and distribution on the market, in particular at a small local production scale.

5.
Anal Sci ; 2024 May 15.
Article in English | MEDLINE | ID: mdl-38748392

ABSTRACT

The development of a highly selective and ultra-sensitive optical sensor for detecting scandium (Sc3+) ions involves incorporating the reagent 2,3-dichloro-6-(3-carboxy-2-hydroxy-1-naphthylazo)quinoxaline (DCHNAQ) into a silica sol-gel thin film on a glass substrate. This innovative approach utilizes tetraethoxy-silane (TEOS) as the precursor, maintaining a sol-gel pH level of 4.5, a water-to-alkoxide ratio of 5:1, and a DCHNAQ concentration of 5.0 × 10-4 M. A detailed exploration of the impact of sol-gel parameters on the sensing capabilities of the developed sensor has been meticulously undertaken. This innovative sensor demonstrates remarkable selectivity in evaluating Sc3+ ions over a dynamic range of 7.5-170 ng/mL, with limits of quantification and detection recorded at 7.3 and 2.20 ng/mL, respectively. Consistent results are achieved with a minimal RSD of 1.47 and 0.94% for Sc3+ ions at 50 and 100 ng/mL, respectively, coupled with a swift response time of three min. Assessments of interference demonstrate a noteworthy preference for Sc3+ions, accomplished by enclosing DCHNAQ within the sol-gel framework and making optimal structural modifications to the doped sol-gel. The sensor offers straightforward regeneration using a 0.25 M EDTA solution, exhibiting complete reversibility. Comparative analysis with other methodologies underscores the efficacy in determining Sc3+ions in various reference materials, including plant leaves, fish, water, alloys, ores, and monazite samples.

7.
Open Vet J ; 14(3): 769-778, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38682138

ABSTRACT

Background: Food poisoning caused by bacterial agents is a worldwide problem, usually accompanied by unpleasant symptoms and may be severe leading to death. Natural compounds from marine algae namely flavonoids may play a role in the remedy of this condition. Aim: This research aims to assess the potency of flavonoids extracted from Enteromorpha intestinalis and Caulerpa prolifera as antibacterial agents. Methods: Enteromorpha intestinalis was collected from Western Libyan Coast and C. prolifera was collected from Farwa Island. The antimicrobial activity and determination of minimum inhibitory concentration of algal flavonoid-containing extracts was performed in vitro against some positive and negative Gram bacteria. Results: Crude extract containing flavonoids from E. intestinalis was more effective than C. prolifera extract against Staphylococcus aureus with antimicrobial essay (25-28 + 1 and 14.5-37.5 + 0.5-1.5), MIC (50 and 50-250 µg/ml), MBC (75 and 75-250 µg/ml). In Bacillus cereus, the antimicrobial assay (19-24.5 + 0.5-1.5: 24 + 1), MIC (50-250 + 100 µg/ml), and MBC (250 and 125 µg/ml). On the other hand, flavonoids containing extract from C. prolifera were more effective than E. intestinalis against Enterohemorrhagic Escherichia coli O157 EHEC O157 (25-28 + 1: 14-18.5 + 0.5-1.5), MIC (100-250:100-500 µg/ml), and MBC (150-250 and 250-500 µg/ml). Salmonella enterica qualitatively combat by flavonoid from E. intestinalis (13.5-14 + 0.5-1: 10.5-13.5 + 0.5-1.5), MIC (100-250: 250 µg/ml), and MBC (100-250: 250 µg/ml). Flavonoids from C. prolifera (4 strains: 2 strains) were effective against S. enterica. Crude flavonoids from both algae were not effective against Bacillus pumilus. Conclusion: Data from this study could conclude that flavonoid extracts from E. intestinalis and C. prolifera could be used against foodborne bacterial agents.


Subject(s)
Anti-Bacterial Agents , Caulerpa , Drug Resistance, Multiple, Bacterial , Flavonoids , Microbial Sensitivity Tests , Flavonoids/pharmacology , Flavonoids/chemistry , Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial/drug effects , Caulerpa/chemistry , Ulva/chemistry , Plant Extracts/pharmacology , Plant Extracts/chemistry , Foodborne Diseases/microbiology , Foodborne Diseases/prevention & control , Foodborne Diseases/veterinary , Animals
8.
Nano Converg ; 11(1): 13, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38551725

ABSTRACT

We report an innovative and facile approach to fabricating an ultrasensitive plasmonic paper substrate for surface-enhanced Raman spectroscopy (SERS). The approach exploits the self-assembling capability of poly(styrene-b-2-vinyl pyridine) block copolymers to form a thin film at the air-liquid interface within the single microdroplet scale for the first time and the subsequent in situ growth of silver nanoparticles (AgNPs). The concentration of the block copolymer was found to play an essential role in stabilizing the droplets during the mass transfer phase and formation of silver nanoparticles, thus influencing the SERS signals. SEM analysis of the morphology of the plasmonic paper substrates revealed the formation of spherical AgNPs evenly distributed across the surface of the formed copolymer film with a size distribution of 47.5 nm. The resultant enhancement factor was calculated to be 1.2 × 107, and the detection limit of rhodamine 6G was as low as 48.9 pM. The nanohybridized plasmonic paper was successfully applied to detect two emerging pollutants-sildenafil and flibanserin-with LODs as low as 1.48 nM and 3.45 nM, respectively. Thus, this study offers new prospects for designing an affordable and readily available, yet highly sensitive, paper-based SERS substrate with the potential for development as a lab-on-a-chip device.

9.
Respir Care ; 69(4): 449-462, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38538014

ABSTRACT

BACKGROUND: In recent years, mechanical power (MP) has emerged as an important concept that can significantly impact outcomes from mechanical ventilation. Several individual components of ventilatory support such as tidal volume (VT), breathing frequency, and PEEP have been shown to contribute to the extent of MP delivered from a mechanical ventilator to patients in respiratory distress/failure. The aim of this study was to identify which common individual setting of mechanical ventilation is more efficient in maintaining safe and protective levels of MP using different modes of ventilation in simulated subjects with ARDS. METHODS: We used an interactive mathematical model of ventilator output during volume control ventilation (VCV) with either constant inspiratory flow (VCV-CF) or descending ramp inspiratory flow, as well as pressure control ventilation (PCV). MP values were determined for simulated subjects with mild, moderate, and severe ARDS; and whenever MP > 17 J/min, VT, breathing frequency, or PEEP was manipulated independently to bring back MP to ≤ 17 J/min. Finally, the optimum VT-breathing frequency combinations for MP = 17 J/min were determined with all 3 modes of ventilation. RESULTS: VCV-CF always resulted in the lowest MPs while PCV resulted in highest MPs. Reductions in VT were the most efficient for maintaining safer and protective MP. At targeted MPs of 17 J/min and maximized minute ventilation, the optimum VT-breathing frequency combinations were 250-350 mL for VT and 32-35 breaths/min for breathing frequency in mild ARDS, 200-350 mL for VT and 34-40 breaths/min for breathing frequency in moderate ARDS, and 200-300 mL for VT and 37-45 breaths/min for breathing frequency for severe ARDS. CONCLUSIONS: VCV-CF resulted in the lowest MP. VT was the most efficient for maintaining safe and protective MP in a mathematical simulation of subjects with ARDS. In the context of maintaining low and safe MPs, ventilatory strategies with lower-than-normal VT and higher-than-normal breathing frequency will need to be implemented in patients with ARDS.


Subject(s)
Respiration, Artificial , Respiratory Distress Syndrome , Humans , Respiration, Artificial/methods , Ventilators, Mechanical , Lung , Tidal Volume , Respiratory Distress Syndrome/therapy
10.
Cureus ; 16(1): e52288, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38357076

ABSTRACT

BACKGROUND/AIM: Cataracts consequence blindness to burden and impose health and economic burdens on communities. Steroid-induced cataracts have scarcely been highlighted in previous literature, creating a demand for reinvestigating this issue among the general population of western Saudi Arabia. METHODS: A cross-sectional study was conducted in 2022 using an online survey distributed among the target participants via social media platforms. The data were gathered and statistically analyzed using IBM Corp. Released 2015. IBM SPSS Statistics for Windows, Version 23.0. Armonk, NY: IBM Corp. software. RESULTS: Overall, 866 respondents (males = 42.5%, females = 57.5%) were enrolled in this survey (mean age = 28.08, SD = 13). The participants' correct responses to questions about steroid-induced cataracts showed inadequate representation (below 50%). Additionally, most of the participants (94.23%) had a poor understanding of steroid-induced cataracts. CONCLUSION: The participants' level of understanding of the risk factors associated with chronic steroid usage and its impact on cataracts was inadequate.

11.
Curr Probl Cardiol ; 49(2): 102212, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37993007

ABSTRACT

BACKGROUND: The importance of coronary computerized tomography angiography (CCTA) in detecting native coronary artery stenosis has been established. However, very few studies investigated the efficacy of CCTA in the assessment of in-stent restenosis (ISR) in symptomatic patients after percutaneous coronary intervention (PCI). AIM OF THE STUDY: To evaluate the value of CCTA in diagnosing ISR. METHODS: We included 102 symptomatic patients with stable angina, presented one to five years after PCI. All patients were subjected to CCTA, and the patients with significant coronary artery disease were directed for invasive coronary angiography (ICA). CCTA results were compared to ICA as the gold standard tool for detecting ISR. RESULTS: In 88 (86.3 %) patients, CCTA could successfully exclude ISR together with the ICA (true negative), but in two cases, ICA detected an ISR which was not detected by CCTA (false negative). In eight patients, CCTA detected ISR. These were confirmed by ICA (true positive) and revascularized. In four patients (3.9 %), ISR was suspected by CCTA but excluded by ICA (false positive). In our study, according to the agreement of CCTA in detection or exclusion of ISR, sensitivity, specificity, PPV, NPV and accuracy were 80.0 %, 96.65 %, 66.67 %, 97.78 %, 94.12 %, respectively. These results were statistically significant (P < 0.001). CONCLUSIONS: In up to 86 % of symptomatic patients with previous PCI, ISR was accurately excluded by CCTA. CCTA was demonstrated by this study as a high yielding tool for ruling out ISR, abolishing the need for more invasive and expensive diagnostic procedures.


Subject(s)
Coronary Artery Disease , Coronary Restenosis , Coronary Stenosis , Percutaneous Coronary Intervention , Humans , Computed Tomography Angiography/methods , Coronary Angiography/methods , Coronary Restenosis/diagnostic imaging , Coronary Restenosis/etiology , Percutaneous Coronary Intervention/adverse effects , Percutaneous Coronary Intervention/methods , Tomography, X-Ray Computed , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/surgery , Predictive Value of Tests
12.
Int J Biol Macromol ; 259(Pt 1): 129080, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38161018

ABSTRACT

Volatile aldehydes have an adverse impact on both human health and the environment, therefore, a fast, straightforward, highly accurate detection technique for the simultaneous detection and removal of several aldehydes is eagerly anticipated. Herein, novel APGF@ZIF-8 and APOF@ZIF-8 sensing materials were developed by coating fluorescent alginate-modified surfactants (APGF and APOF) into the ZIF-8 MOFs to produce quite porous fluorescent sensors (SBET up to 1519 m2/g). The detection capacity of the prepared sensors for benzaldehyde, glyoxal, formaldehyde, and acetaldehyde has been examined. The detection mechanism was suggested as hydrogen bonding formation between the sensors and volatile aldehydes as confirmed by Gaussian calculations. All the fluorescence spectra of aldehydes display remarkable linear detection relationships in the range of 0.05-200 µM with the limits of detection (LOD) values in the range of 0.001-0.18 µM (0.106-10.44 ppb). These sensors were utilized successfully to detect multiple volatile aldehydes in river water samples with satisfactory recoveries of 96-107 %. Interestingly, fluorescent APGF@ZIF-8/CS and APOF@ZIF-8/CS films as portable disposable removal techniques for benzaldehyde, glyoxal, formaldehyde, and acetaldehyde from water were fabricated. APOF@ZIF-8/CS exhibited an excellent formaldehyde adsorption capacity of 58.30 mg/g and an adsorption removal efficiency of 93.5 %. The adsorption process of biosorbent on various aldehydes was fitted by Freundlich adsorption isotherm. The adsorption kinetics followed Pseudo-second-order kinetic model.


Subject(s)
Metal-Organic Frameworks , Water Pollutants, Chemical , Humans , Aldehydes , Benzaldehydes , Water , Adsorption , Alginates , Water Pollutants, Chemical/analysis , Coloring Agents , Formaldehyde , Acetaldehyde , Glyoxal
13.
Cureus ; 15(12): e50326, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38155979

ABSTRACT

Lactose intolerance is a condition causing an inability to absorb and digest lactose leading to gastrointestinal symptoms such as abdominal pain, diarrhea, and flatulence. Because of the similarities between lactose intolerance and cow's milk allergy, it is becoming necessary to increase physicians' understanding of these two diseases. Consequently, we aimed to determine the level of knowledge of lactose intolerance and cow's milk allergy among medical students. An electronic survey was distributed to 399 medical students at two universities in Saudi Arabia from October to November 2022. The majority of the respondents had an inadequate knowledge of both lactose intolerance and cow's milk allergy (99.75% and 97.99%, respectively). According to the study's results that showed a lack of awareness among health-related students, further studies and awareness programs are highly recommended.

14.
Biol Trace Elem Res ; 2023 Dec 22.
Article in English | MEDLINE | ID: mdl-38129339

ABSTRACT

Metal pollution is a major environmental concern worldwide, especially in Egypt. The aquaculture industry uses widespread artificial feeds to stimulate fish production, leading to metal accumulation in the aquatic environment. Heavy metal concentrations (HMCs) in sediments, water, and tissues were studied to study the effect of pollution levels on heamatological, and biochemical, immunological aspects of farmed fish as well as on human health. Results declared that the HMC levels in the water and sediment were significantly different between El-Sharkia and Kafr El-Sheikh fishponds (T-test, p < 0.05). This was supported by the metal pollution index in the water and sediment, indicating that El-Sharkia fishponds (ES fishponds) were more contaminated than Kafr El-Sheikh fishponds (KES fishponds). Also, HMCs in fish tissues were significantly increased in fish cultivated in ES fishponds than in KES fishponds. Haematological, immunological, and biochemical alterations of Bolti (Oreochromis niloticus) and Topara (Chelon ramada) fish were significantly different within the different fish species as well as the different fishponds. From the human health perspective, the THQ-HMC and HI-HMC associated with the consumption of muscle suggest a safe non-carcinogenic risk to human health. In contrast, cadmium poses a cancer risk to children who consume the muscular tissue of Bolti fish from ES fishponds, which should be regarded as a warning sign based on data indices and a human health perspective. In order to minimise HMC pollution in the aquaculture sector, it is advisable to take possible assessments and carry out continuous monitoring considering international WHO/FAO assessments.

15.
Sci Rep ; 13(1): 22688, 2023 12 20.
Article in English | MEDLINE | ID: mdl-38114741

ABSTRACT

The current conflict in Sudan severely hinders the accessibility of health services across the country. To address this, several initiatives were proposed including offering services using teleconsultations. This study aimed to assess Sudanese doctors' teleconsultation experience, perception, and concerns during the recent conflict. This cross-sectional survey focused on Sudanese medical officers, residents, specialists, and consultants living inside or outside the country having a practice license from the Sudan Medical Council and conducting teleconsultations with Sudanese patients during the conflict period. The questionnaire was distributed to personal and professional contacts and via social media platforms in the English language among doctors who provided teleconsultation during the conflict. Data analysis was performed using the Statistical Package for Social Sciences software version 26. The study enrolled 2463 clinicians from 17 different specialties, and females represented more than half the sample (56.8%). Internal medicine was the most frequent specialty (36.1%) and the majority (68.7%) of clinicians had less than 5 years of work experience. Voice call was the most frequent platform (50.1%) used for teleconsultation during the conflict and had the highest convenience score (p < 0.01), whereas messaging platforms had the lowest score. Most clinicians (73.3%) agreed that teleconsultations created a trusted patient-physician relationship and provided good-quality care (61.8%). However, 85.1% highlighted the importance of physical touch in medical practice. Clinicians were concerned that incomplete information (81.4%), missed diagnosis (76.8%), medicolegal problems (71.0%), and prescription errors (68.4%) could arise with teleconsultations. Most respondents (70.7%) emphasized the importance of continuing to offer teleconsultation even after the war abated. In conclusion, physicians who participated in the current study agreed that teleconsultation provided quality care even in this dire crisis in Sudan. Based on our study findings, we recommend upscaling telemedicine interventions including teleconsultations at the national level. This would require unified coordination efforts of a wide mix of stakeholders to address concerns identified in the current study.


Subject(s)
Physicians , Remote Consultation , Telemedicine , Female , Humans , Sudan , Cross-Sectional Studies
16.
J Mol Model ; 30(1): 16, 2023 Dec 29.
Article in English | MEDLINE | ID: mdl-38157075

ABSTRACT

CONTEXT AND RESULTS: Site-directed spin labeling (SDSL) combined with electron paramagnetic resonance spectroscopy methods has been successfully used to predict the structures of nucleic acids. These methods measure the distances between spin labels yielding distance equations that are solved using numerical algorithms to provide one or several structural predictions. In this work, the minimum number of SDSL distance measurements and distance measurement types required to predict a unique nucleic acid structure were investigated. Our results indicate that at least six distance measurements should be obtained given that the distance measurements do not connect one SDSL on one arm with more than three SDSLs on the other arm. Moreover, there may be a preference for 1-to-1 SLs distance measurements rather than 1-to-many SLs as the latter was linked to undefined structures discussed in this study. METHODS: Pairs of double-helical arms of nucleic acid were simulated using the finite element software Pro/ENGINEER (PTC Inc., Boston, MA). In each simulation, a specific SDSL distance measurement plan was adopted and the resulting structure was tested for movability. Immovable structures indicate that this plan will potentially result in a unique structural prediction of the nucleic acid. All the possible plans for SDSL distance measurements were investigated either by direct measurement or by extrapolation.


Subject(s)
Nucleic Acids , Spin Labels , Electron Spin Resonance Spectroscopy/methods , Algorithms
17.
RSC Adv ; 13(49): 34618-34629, 2023 Nov 22.
Article in English | MEDLINE | ID: mdl-38024967

ABSTRACT

A novel optical sensor has been developed to measure selenium ions. The sensor membrane was created by mixing xylenol orange (XO) and sodium tetraphenylborate (NaTPB) with a plasticized poly(vinyl chloride) membrane that contained o-nitrophenyl octyl ether (o-NPOE) as a plasticizer. XO was previously established for use in a colorimeter to measure selenium in water and other media. At pH 6.6, the color of the detecting membrane changed from orange to pink when in contact with Se4+ ions. Various variables affecting the uptake efficiency were evaluated and optimized. Under optimum conditions (i.e., 30% PVC, 60% o-NPOE, and 5.0% of both XO and NaTPB for 5.0 min as the response time), the proposed sensor displayed a linear range 10-175 ng mL-1 with the detection and quantification limits of 3.0 and 10 ng mL-1, respectively. Also, the precision (RSD%) was better than 2.2% for six replicate determinations of 100 ng mL-1 Se4+ in various membranes. For the detection of Se4+, the selectivity of the sensor membrane was investigated for a number of possible interfering inorganic cations, but no appreciable interference was found. With the use of a 0.3 M HCl solution, the sensor was successfully restored, and the response that may have been reversible and reproducible exhibited an RSD% of less than 2.0%. The sensor has been successfully used to analyze Se4+ ions in environmental and biological materials.

18.
Saudi J Anaesth ; 17(4): 523-532, 2023.
Article in English | MEDLINE | ID: mdl-37779559

ABSTRACT

Advancements in modern health care over 20 years have substantially increased the average lifespan in developed countries, and the fastest growing population is the elderly population. The proportion of people in Saudi Arabia aged 60 or more is predicted to be 25 percent of the total population of 40 million by the end of 2050. Moreover, the number of people aged 80 or more is expected to reach 1.6 million or 4 percent of the total population in the same period. Improvements in surgical techniques, anesthesia, and intensive care units make surgical interventions in older and sicker patients possible. It is estimated that over half of the population older than 65 years will require surgical intervention at least once during the remainder of their lives. Therefore, elderly patients are becoming an even larger part of anesthetic practice. Regional anesthesia (RA) is frequently used in elderly patients, especially during orthopedic surgery, genitourologic and gynecologic procedures, and hernia repair. Although age can no longer be considered a contraindication to anesthesia and surgery, anesthesia-related morbidity and mortality remain higher among elderly than among young adult surgical patients. Undoubtedly, peripheral nerve (PN) blocks improve analgesia and reduce opioid consumption and their associated side effects. This is beneficial in the perioperative care of elderly patients who may have less physiologic reserve to withstand the side effects of general anesthesia (GA).

19.
Foods ; 12(20)2023 Oct 17.
Article in English | MEDLINE | ID: mdl-37893704

ABSTRACT

Dates are highly perishable fruits, and maintaining their quality during storage is crucial. The current study aims to investigate the impact of storage conditions on the quality of dates (Khalas and Sukary cultivars) at the Tamer stage and predict their quality attributes during storage using artificial neural networks (ANN). The studied storage conditions were the modified atmosphere packing (MAP) gases (CO2, O2, and N), packaging materials, storage temperature, and storage time, and the evaluated quality attributes were moisture content, firmness, color parameters (L*, a*, b*, and ∆E), pH, water activity, total soluble solids, and microbial contamination. The findings demonstrated that the storage conditions significantly impacted (p < 0.05) the quality of the two stored date cultivars. The use of MAP with 20% CO2 + 80% N had a high potential to decrease the rate of color transformation and microbial growth of dates stored at 4 °C for both stored date cultivars. The developed ANN models efficiently predicted the quality changes of stored dates closely aligned with observed values under the different storage conditions, as evidenced by low Root Mean Square Error (RMSE) and Mean Absolute Percentage Error (MAPE) values. In addition, the reliability of the developed ANN models was further affirmed by the linear regression between predicted and measured values, which closely follow the 1:1 line, with R2 values ranging from 0.766 to 0.980, the ANN models demonstrate accurate estimating of fruit quality attributes. The study's findings contribute to food quality and supply chain management through the identification of optimal storage conditions and predicting the fruit quality during storage under different atmosphere conditions, thereby minimizing food waste and enhancing food safety.

20.
J Fr Ophtalmol ; 46(10): 1265-1266, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37666738
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