We evaluated the effect of a behaviorally enhanced quality improvement intervention in reducing the number of antibiotic prescriptions written for antibiotic nonresponsive acute respiratory infections (ARIs). A secondary objective was identifying whether a reduction in inappropriate antibiotic prescriptions, if present, persisted after the immediate implementation of the intervention.Nonrandomized, quasi-experimental study conducted from January 2017 through February 2020.University of California, Davis Health outpatient clinics. In total, 21 pediatric, family, and internal medicine practices in 10 cities and towns were included.International Classification of Diseases, Tenth Revision codes consistent with antibiotic nonresponsive ARI diagnoses.Patients evaluated by a participating physician at an enrolled practice site during the study period with diagnoses (primary and secondary) from the A behaviorally enhanced quality improvement intervention to reduce inappropriate prescribing for antibiotic nonresponsive ARI.P = .001) following the intervention. We detected no significant change in the month-to-month trend after the intervention was implemented (P = .87), indicating that the reduction was sustained throughout the postintervention period.In total, 63,028 eligible patient visits across 21 locations were included in the analysis. The most frequently prescribed antibiotic for antibiotic nonresponsive ARI was azithromycin , followed by amoxicillin (n = 924). Overall, the intervention was associated with an immediate 46% reduction in antibiotic prescriptions for antibiotic nonresponsive ARI (Our findings demonstrate that a behaviorally enhanced quality improvement intervention to reduce inappropriate prescribing for antibiotic nonresponsive ARI in ambulatory care encounters was successful in reducing potentially inappropriate prescriptions for presumed antibiotic nonresponsive ARI. Clostridium difficile or other multidrug-resistant pathogens, making it a major public health concern. The use of antibiotics, including inappropriate and overuse, accelerates the natural selection of antibiotic-resistant bacteria, which cause an estimated 35,000 deaths in the United States each year. Encouraging judicious prescribing of antibiotics effectively reduces unnecessary antibiotic exposure, improves antibiotic prescribing practices, and addresses the crisis of emerging antibiotic resistance.Inappropriate use of antibiotics increases healthcare utilization and cost as well as a patient’s risk of adverse drug events and infection by  In 2019, ∼251 million oral antibiotic prescriptions were written in outpatient settings. The Centers for Disease Control and Prevention estimates that outpatient settings account for 85%–90% of antibiotic prescriptions in the United States, and that ∼30% of those outpatient prescriptions are unnecessary. One of the most common examples of unnecessary antibiotic prescriptions in outpatient settings is for viral respiratory infections. Even though ∼50% of prescriptions written for respiratory infections are inappropriate, programs targeting the unique needs of outpatient facilities have had limited success.Antimicrobial stewardship programs are required in hospitals and long-term care facilities by the Centers for Medicare and Medicaid Services and the Joint Commission, and efforts are underway to develop programs for outpatient facilities. Several studies have shown that interventions grounded in behavioral economics and decision science are effective in reducing inappropriate antibiotic prescribing for ARI in primary care and outpatient facilities. These behavioral interventions generally leverage individual accountability and social norms by utilizing feedback, nudges, and peer comparisons to improve prescribing outcomes. Peer comparisons have been shown to improve prescribing outcomes and to be sustained after the intervention for at least 12 months.Providers in outpatient facilities face unique day-to-day challenges to antibiotic decision making. Issues such as frequent interruptions, patient expectations, and the high volumes of patients seen per hour compound with the need to make quick decisions with limited diagnostic data.In this study, we evaluated the effect of a behaviorally enhanced quality improvement intervention in reducing inappropriate antibiotic prescribing for antibiotic nonresponsive acute respiratory infections (ARIs) across a regional outpatient health system network of primary care clinics.This study was conducted as a nonrandomized quasi-experimental study. The intervention was implemented at University of California–Davis Health outpatient clinics and was deemed exempt from institutional review board requirements based on its designation as a quality improvement project. In total, 21 pediatric, family, and internal medicine practices in 10 cities and towns were included in the intervention roll out. The preintervention period was January–December 2017, the intervention was implemented across clinic sites from January to December 2018, and the postintervention period was January 2019 to February 2020. Data on patient visits were collected from a central electronic health record (EHR) database.International Classification of Diseases, Tenth Revision (ICD-10-CM) codes consistent with antibiotic nonresponsive ARI diagnoses with consideration of secondary diagnostic codes as modifiers, adapted from the MITIGATE tool kit. The MITIGATE tool kit is based on an adaptation from evidence-based literature (see tool kit background) and the Center for Disease Control and Prevention (CDC) Core Elements of Outpatient Antibiotic Stewardship. The following conditions were targeted for reducing antibiotic prescribing by the intervention: nonsuppurative otitis media, acute nasopharyngitis, laryngitis, supraglottitis, croup, influenza, viral pneumonia, viral bronchitis, unspecified bronchitis, bronchiolitis, lower respiratory tract infection unspecified, vasomotor and allergic rhinitis, chronic nasopharyngitis, bronchitis, not specified as acute or chronic, and asthma (see MITIGATE toolkit Table Eligible visits included those with diagnoses (primary and secondary) from the  quality metrics on acute bronchitis. However, we broadened them to include all other antibiotic nonresponsive ARIs as well as pediatric and geriatric populations. A patient visit was eligible for inclusion if (1) the patient was evaluated by a participating physician at an enrolled practice site and was assigned an ICD-10 code consistent with antibiotic nonresponsive ARI and (2) the visit occurred during the preintervention, intervention, or postintervention period. Visits were excluded from the primary analysis if the patient had either a nonacute respiratory bacterial infection diagnosis or an antibiotic-appropriate ARI diagnosis that co-occurred with their qualifying diagnosis at the visit, such as urinary tract infections or pneumonia. The sets of exclusionary diagnoses that were used to identify antibiotic nonresponsive ARIs are listed in the public MITIGATE tool kit, with the addition of the ICD-10 for acne to include for antibiotic use concordant with guidelines for management of acne.The parameters for identifying antibiotic nonresponsive ARIs were intended to be congruent with existing Healthcare Effectiveness Data and Information Set and National Quality ForumThe primary outcome measure for this analysis was the number of all antibiotics reasonably assumed to be prescribed for an antibiotic nonresponsive ARI at each clinic, per month. Antibiotics were identified by pharmacy therapeutic class through the EHR if the prescription occurred the same day or within 3 days of the office encounter. Non–office-based visits including phone encounters, patient messaging, or orders only were excluded. If an individual was prescribed 2 antibiotics at the same encounter, both antibiotics were included in the monthly total if both were accompanied by an ICD-10 code consistent with an antibiotic-nonresponsive ARI. The study was designed to test whether the antibiotic stewardship program resulted in an immediate statistically significant decrease in the number of antibiotic prescriptions written for antibiotic-nonresponsive ARI. We also sought to determine whether a reduction in inappropriate antibiotic prescriptions, if present, persisted after the immediate implementation of the intervention. Several of the core elements were included in the behaviorally enhanced quality improvement intervention using implementation tools feasible in the acute-care setting and accepted by local physicians. Strategies incorporated include leadership support, data reporting and feedback through clinic comparisons and physician feedback, educational strategies, and identification of a site champion.The adapted intervention incorporated strategies from the CDC Core Elements of Outpatient Antibiotic Stewardship, which provides a recommended framework for implementing stewardship in outpatient settings.Our program was sponsored by the leadership of the primary care clinics as well as the chief quality officer and formal outpatient antibiotic stewardship program. The intervention included educational sessions, sharing of data by clinic (comparisons), as well as patient and physician educational materials. Each month the antibiotic prescribing practices for nonresponsive ARI at each clinic were aggregated from the EHR and sent to the champions and medical directors for clinic comparisons. Champions were identified for each of the clinics by the individual site medical directors and were tasked with leading provider education and advocating for antimicrobial stewardship. Champions collaborated with clinical and operations staff to adapt each of the intervention components to ensure that they were consistent with local systems, policies, and standards. These customizations ensured that the program fit within the organization culture and workflow. A plan was developed for implementing and monitoring each of the components. Standard operating procedures were refined and shared with staff.The intervention period began with resident education and staff meetings in January 2018. Education was provided via e-mail as well as through individual site meetings with each of the clinic providers. In one clinic, the hospital-based internal medicine clinic-public commitment posters with physician signatures were posted. Academic detailing of outlying providers using individual provider data was performed by the medical directors or champions in select clinics where baseline and subsequent antibiotic prescribing rates were higher.The number of eligible visits and the outcome variable, number of antibiotic prescriptions written for antibiotic nonresponsive ARI, were aggregated at the month level, resulting in 38 data points. The rate of antibiotic nonresponsive ARI prescriptions was explored for all clinics with a scatter plot and line of best fit to visualize the slope direction and change across the study period prior to modeling Fig. . DescripThe intervention effect was assessed using an interrupted time series (ITS) analysis over the study period. A sequential period variable, the outcome variable, the location-specific intervention time point, and a location-specific time after the intervention variables were included in the model. The period is a continuous variable indicating the time in months from the start of the study period. The location-specific intervention is an indicator variable for time occurring before the intervention and the time occurring after the intervention. Depending on what month the intervention was implemented for each location, each clinic has periods with intervention = 0, indicating the points in the study considered before the intervention for that specific clinic, and an intervention = 1, indicating the points in the study considered after the intervention. Time after the intervention is a continuous variable counting the number of months after the intervention implementation for each location. Seasonality was controlled for in the model using the CDC-defined peak of winter respiratory virus season, December through March. was performed using a negative binomial, mixed-effects model of the monthly data  using SAS software . The intervention and time after the intervention variables accounted for the location-specific time points of implementation. Period, intervention, and time after the intervention were included as fixed effects . To account for the rollout of the intervention across the clinics during the intervention period, individual clinics could have unique starting points as well as different immediate and gradual effects of the intervention by including random intercepts, intervention, and time after intervention terms. A random residual with an autoregressive variance structure was used to account for the correlation of measurements over time, across clinics, and overdispersion. The total number of eligible visits at each clinic, each month was used as an offset variable (denominator for the primary outcome of interest) in the model to compare rates.A segmented regression techniqueP values < .05 were considered significant.The intervention variable was assessed to estimate the immediate intervention effect. This effect indicates the interventions’ immediate impact on antibiotic nonresponsive ARI antibiotic prescribing at a clinic and is denoted by a change in level, or y-intercept, immediately following the intervention implementation. The long-term intervention effect is assessed by evaluating the time after intervention variable. This effect indicates whether the intervention impact persisted after the immediate intervention effect into the postintervention period. The long-term intervention effect is denoted by a difference in slope from the preintervention period to the postintervention period. The differential impact of the intervention was assessed for adult and pediatric providers. Individual clinics were combined if they were in the same city or town to maintain confidentiality. All statistical tests were 2-sided and In total, 21 clinics across 10 cities and towns were enrolled in the intervention. From January 2017 through February 2020, a total of 63,028 eligible patient visits occurred in the enrolled clinics. The average number of eligible patient visits each month was 166 visits  over the study period. The average patient age was 44 years . At the start of the study, the percentage of visits in which an antibiotic was prescribed for antibiotic nonresponsive ARI ranged from 3.7% to 34.2%. During the preintervention period, an antibiotic was prescribed, on average, for 11.5%  of eligible visits. By the end of the study period, the percentage of antibiotic nonresponsive ARI antibiotic prescriptions had decreased to a low of 1.2% of visits and a high of 18% of visits. During the postintervention period, an average of 5.8%  of eligible antibiotic nonresponsive ARI visits had an antibiotic prescribed. The most frequently prescribed antibiotic over the study period was azithromycin , followed by amoxicillin (n = 924). See Table P = .20). The immediate intervention effect indicated a 46% reduction in antibiotic nonresponsive ARI antibiotic prescriptions or 0.54 times  as many antibiotic nonresponsive ARI antibiotics prescribed after the intervention, after controlling for seasonality. The immediate intervention effect varied by location. Among clinics at one of the suburban locations, antibiotic prescribing immediately after the intervention was 0.56 times  what it was before the intervention, a 55% reduction (P = .001). One larger suburban location saw a statistically significant increase in the number of antibiotic nonresponsive ARI antibiotic prescriptions immediately after the intervention.Overall, the intervention was associated with a statistically significant decrease in antibiotic nonresponsive ARI antibiotic prescribing. The intervention impact did not differ among adult and pediatric providers (P = .20). The slope during the postintervention period did not statistically significantly differ from the preintervention period slope . See Table The long-term intervention effect indicated no statistically significant trend in the number of antibiotic-nonresponsive ARI antibiotics prescribed across all clinics during the postintervention period. We detected no statistically significant trend in prescribing rates during the preintervention period  are initiatives from healthcare teams that focus on optimizing antibiotic use and are aimed at enforcing practical behavioral interventions to improve excessive antibiotic prescribing. Each ASP can be uniquely configured to target specific components throughout the prescribing process to prevent inappropriate use, ranging from simple steps  to more intensive processes . Overall, there is sufficient evidence to support the effectiveness of behavioral interventions in reducing overuse of antibiotics regardless of the exact mechanism applied, though important healthcare settings have been understudied, such as the community and rural settings proposed in this protocol.Antibiotics are lifesaving medications that are vital to the treatment of severe infections. To maintain efficacy of the antibiotic supply, emphasis has been placed on improving the judicious use of antibiotics. Unfortunately, individual patient–physician decisions are not always swayed by the knowledge that antibiotics do not treat viruses or the knowledge that overprescribing will create major public health problems down the line. Healthcare professionals have been taught to do no harm, and yet, many underestimate the potential negative effects of antibiotics and assume that these risks do not outweigh the need to treat the patient immediately. In turn, many patients feel that an antibiotic prescription is a requisite part of going to the doctor. And because physicians are increasingly judged and compensated based on patient satisfaction, they often feel pressured to prescribe antibiotics even when these medicines are not likely to work.Core Elements of Outpatient Antibiotic Stewardship, nudging elements such as clinic comparisons with prescribing data, and antibiotic commitment posters. Also, the successful use of EHR reports in the intervention highlights the need for prioritization of information technology support to obtain data reports from EHR.Our findings could be a model for other large integrated health systems in rolling out stewardship and other quality improvement interventions. Furthermore, while this intervention may not be applicable to all healthcare settings, certain key elements could be scaled for additional settings and populations. These could include the importance of leadership support as outlined in the CDC The findings of this study are promising, but the study is not without limitations. Quasi-experimental studies are strong designs when randomized controlled trials are not feasible. However, clinics in our study were not randomized, and were appointed intervention periods based on availability and convenience. A more rigorous design would have been a cluster randomized trial, but the intervention rollout was more palatable to clinical leadership. Furthermore, utilizing the rollout design rather than randomizing intervention and control clinics, supported the study goal of reducing antibiotic misuse for antibiotic nonresponsive ARIs. Additionally, we were unable to control or account for any potential Hawthorne effect, physicians changing prescribing behaviors or being influenced by hearing about the intervention prior to the implementation in their clinic. Although this could affect the results at any 1 clinic and may begin to explain the unexpected increase in antibiotic nonresponsive ARI antibiotic prescriptions following the intervention at 1 large suburban clinic, the intervention was still associated with a statistically significant decrease in antibiotic nonresponsive ARI antibiotic prescriptions. This indicates that any potential Hawthorne effect was insignificant. In addition, we did not include non–office-based visits, which may have higher rates of antibiotic prescribing, and we did not confirm viral etiology because collecting laboratory information was outside the project scope. Agent-specific interventions could be beneficial in reducing inappropriate antibiotic prescribing. The impact of agent-based stewardship programs should be assessed and compared with stewardship programs focused solely on the decision to treat or not to treat.Further studies are needed to evaluate antibiotic prescribing for non–office-based visits and to determine the best combination of interventions to encourage judicious antibiotic prescribing in the outpatient setting. From this study, we were unable to identify what the most effective components of the intervention were. It is possible that more “social” interventions similar to the public commitment posters, peer comparisons, and champions efforts can be implemented to produce an even greater outcome regarding decreasing inappropriate antibiotic use. Individual provider feedback on the stewardship components after the intervention could strengthen our understanding of how to best develop and implement behavioral interventions. Stewardship programs should work toward decreasing antibiotic overuse while maintaining a good patient–physician relationship. Patients often demand medication despite the inappropriateness of the prescription, so efforts should focus on facilitating better communication between the prescriber and the patient. Finally, reducing inappropriate antibiotic prescribing for nonresponsive ARI was the primary goal of this study, and we did not focus on the selection of particular agents. However, azithromycin was the most prescribed antibiotic over the study period, and other studies have reported that >50% of macrolide prescriptions may be inappropriate.


The metal ions using atomic absorption spectroscopy method (AAS) were determined. The use of MS-AB 113 ensures a high selectivity of divalent ions while the XAD7HP-AB 113 had excellent affinity for Cr3+ in the presence of Zn2+ and Mn2+. As a consequence, two advanced polymers, i.e., MS-AB 113 and XAD7HP-AB 113 that provide huge capacity for removal of Zn2+, Mn2+ and Cr3+ from acid polluted wastewater were obtained.This research had two stages of development: during the first stage, the purpose of the research was to evaluate the adsorption properties of the natural polymer represented by shredded maize stalk (MS) and by Amberlite XAD7HP (XAD7HP) acrylic resin for removal of toxic diazo Acid Blue 113 (AB 113) dye from aqueous solutions. The AB 113 concentration was evaluated spectrometrically at 565 nm. In the second stage, the stability of MS loaded with AB 113 (MS-AB 113) and of XAD7HP loaded with AB 113 (XAD7HP-AB 113) in acidic medium suggests that impregnated materials can be used for selective removal of metal ions (Cr X+) removal new chelate materials have been developed  naphthalen-1-yl] diazenyl] naphthalene-1-sulfonate) and acetone (Ac) from Sigma Aldrich were purchased. The XAD7HP is acrylic ester resin being proper for high molecular organic compounds and metals is only moderately polar. Short information about the characteristics of XAD7HP in the data sheet  and in pThe UV-Vis spectra of the AB 113 were recorded using the DR/5000 TM spectrometer  in quartz cuvettes (1 cm) in the 200–800 nm range, with 100 nm/min scanning speed, using ultrapure water as reference.The PinAAcle 900T atomic absorption spectrometer  was used to determine the concentration of metal ions in the supernatant solution before and after contact with the MS-AB 113 and XAD7HP studied.The masses of materials  and AB 113 were weighed using the XT220A Precise Gravimetrics scale, Dietikon, Switzerland.The pH of the supernatant solutions was also measured with the HI 255 pH meter, Hanna Instruments, Nijverheidslaan, Belgium.To obtained ultrapure water (18 MΩ/cm), an Ultra-Clear system was used .The MS (1-mm particle) swollen in ultrapure water was placed in 2.5 × 25 cm glass column. MS was purified with 4 M HCl solution at 0.6 mL/min flow rate . After aAmberlite XAD7HP resin was added in a Berzelius glass. The resin was washed several times with ultrapure water, decanting the solution until the water became clear. The resin was then allowed to swell in water for 24 h. The swollen resin was transferred to a 2.5 × 25 cm glass column over which a 4 M HCl solution was passed at 0.6 mL/min flow rate . SubsequThe dried MS and XAD7HP resin were kept in the desiccator throughout the studies.To study the influence of MS and XAD7HP dose, 0.25, 0.5 and 1 g were chosen for each material studied. Furthermore, 0.04 L of 100 mg/L AB 113 was added over each sample. The obtained mixtures were stirred for 3 h in the mechanical stirrer horizontally at 175 rpm at 25 ± 2 °C). At the end of the experiment the mixtures were filtered and spectrometrically analyzed.The quantity of AB 113 adsorption per unit of XAD7HP and MS mass were determined using Equation (1).X+ on the polymers materials and materials impregnated with AB 113 were evaluated using Equation (2)  benzamide) and LID  acetamide), were used for XAD7HP impregnations. The new materials obtained, i.e., XAD7HP-PHA and XAD7HP-LID, were tested for Asand Pb2+ . Further removal ,36. Cipef 90 min . Davides amounts .X+) is released into solution in the form of AB 113-MX+ if the AB 113 with MX+ forms a stabile complex; or (ii) under the action of the regeneration agent are released in solution only MX+ and AB 113 still remaining loaded in the mass of material [The following hypothesis for the metal ions recovery from MS-AB and 113 XAD7HP–AB 113 can be taken into consideration: (i) by the influence of the regeneration agent the metallic ion  released the most in 2 M HCL solution. Moreover, the Mn2+ and Zn2+ existing in solid samples were also desorbed by the 2 M HCl—For XAD7HP-AB 113 resin loaded with M2+ and Pb2+ was regenerated with acidic solutions (3 M HNO3). Furthermore, 93% Cu2+ and 89% Pb2+ was recovered from maize stalk mass in liquid phases [2+ and 89% Fe3+ are released from maize stalk mass with 4 M HCl [5+, Cd2+, Co2+, Cr3+, Fe3+, Mn2+, Mo6+, Ni2+, Pb2+, Sb3+, V2+, Zn2+, Tl3+ and Sr2+ retained onto maize stalk with 1 and 4 M HCl was investigated. The influence of acidic solutions obeyed the theoretical rules when 4 M HCl was used; the majority of metal ions were released in liquid phases [2+ and Ni2+ from CELL-GLY was evaluated with 0.1 M HCl and more than 95% of each metal was recovered [Exhausted maize stalk with Cud phases . Further 4 M HCl . The ched phases . As presecovered .3+, Zn2+ and Mn2+ from acidic polluted wastewaters. Furthermore, following the desorption studies, the removed metals can be recovered by applying the ecological processes developed in this study. Taking into account capacity and selectivity, this article proposed polymeric materials, i.e., XAD7HP resin and MS for azo dye and polymers loaded with AB 113 to metal ions removal. Furthermore, the XAD7HP polymer resin can be a good choice if the acquisition cost is comparatively higher with MS. On the other hand, MS is easy to obtain  and represents a sustainable material for ecofriendly technologies.In this research, eco-friendly materials were employed for removal of the first pollutant (AB 113), and subsequently to remove secondary pollutants . The optimum dose for efficient AB 113 removal was chosen to be 0.25 g for MS and XAD7HP by proposed procedure. It was also observed that the MS and XAD7HP have good adsorption capacity for AB 113. EtOH was used as optimal solvent for AB 113 desorption from both polymeric materials studied. In addition, only 5% AB 113 was found in 2 M HCl liquid phases of MS-AB 113. The XAD7HP-AB 113 under 2 M HCl acidic action released 3.1% AB 113. All these results suggested that MS-AB 113 and XAD7HP-AB 113 have chemical stability in acidic medium up to 2 M HCl. The MS-AB 113 and XAD7HP-AB 113 materials having chelating properties were obtained by physical π-π interactions. It was proved that the MS-AB 113 and XAD7HP-AB 113 are relatively easy to obtain. Based on those results, MS-AB 113 and XAD7HP-AB 113 can be recommended for removal of Cr


In order to estimate the crack depth in concrete using time-of-flight, finite element analysis and experiments were performed on non-cracked concrete blocks and 45 mm and 70 mm vertical cracks. As a result of measuring the time-of-flight change by changing the positions of the transmitter and receiver, it was confirmed that the finite element analysis results agreed with the experimental results, and high accuracy was confirmed by various formulas for calculating the depth of defects using the obtained experimental measurements for comparison. In addition to the verification of the simulation and experimental theory, research was conducted through actual field cases, and methodologies for crack detection and depth evaluation for concrete structures were presented, and furthermore, the expected effects of improving the soundness and safety of structures were shown. Compared to other structural materials, concrete structures have superior strength, durability, water tightness, steel protection performance, etc. They also have the advantage of being pourable without being greatly constrained by shape. However, there are also vulnerabilities that are prone to cracks, which may occur due to insufficient safety inspection and maintenance as the period of use elapses, due to design errors or defects in construction. If left unattended, cracks in concrete can affect the safety of the structure and result in crack growth due to several factors, including salt penetration. It is very important to manage cracks in order to secure the integrity of a concrete structure. If not managed through periodic inspection and proper maintenance, cracks can grow and lead to leakage or collapse.One method for evaluating cracks in concrete structures with ultrasound is directly examining them with a pulser and receiver at opposite sides of the structure . HoweverThe most important factors in the concrete crack inspection are the crack width, length, and depth ,6,7,8. CAccording to the British Standard for UPV Measurement of Concrete (BS 1881), the indirectly transmitted UPV is 5–20% lower than the direct transmission velocity, which mostly depends on the concrete quality. Jones  describeThe American Standard for UPV Measurement of Concrete (ASTM C 597) does not recommend measuring the UPV by indirect transmission unless accessible from one surface of the material. It indicates that indirect transmission is a characteristic of the layer close to the surface. This is because only the value obtained from the direct transmission can be expressed. Currently, there is no ASTM standard for indirect UPV measurement.M. Sansalone et al. proposed a technique for determining the thickness of concrete elements and finding defects in concrete through P-wave velocity measurement technology, by applying indirect transmission in concrete. Two transducers were placed on a concrete surface, and an impact was generated at a point along a line drawn between the axes of the two transducers. The UPV was calculated as the ratio of the distance between the transducers and the ultrasonic propagation time between the transducers, and recommendations were made for the transducer spacing when determining the UPV . IndirecN. M. Sutan et al. conducted a comparative experiment with direct and indirect methods of UPV to detect concrete defects. Through this, a relational expression that can find voids in concrete and estimate the depth was verified. After 3, 7, 14, and 28 days elapsed, five Grade-40 concrete specimens were fabricated, and the accuracy of the two methods was confirmed. As a result, the direct transmission showed more convenient and satisfactory results in the sensitivity of judging the location of a defect than the indirect transmission, but the ability to determine the depth of the void was lacking. Therefore, only indirect transmission was possible when both the depth and location of the void had to be determined, and the accuracy was 60–99% depending on the curing period . HoweverThe aims of this study were the following. (1) Simulation was done using the UPV method for concrete blocks as a new approach that could not be confirmed in previous studies. (2) We compared and verified the accuracy of measurements obtained through theoretical and practical experiments. (3) We conducted research on actual field cases as well as verification of the simulation and experimental theory. (4) We present methodologies for crack detection and depth evaluation for concrete structures. We confirmed their applicability in actual sites.This section covers some techniques used in crack detection, depth measurement studies, and results that were confirmed through experiments. It summarizes the composition of ultrasonic inspection equipment, transducer and frequency determination, concrete specimen experiment, simulation for concrete ultrasonic examination modeling, and examination results for cracks in actual structures.A compression wave is generated by an electro-acoustic transducer in contact with a concrete surface. This pulse passes through the concrete and the second transducer, which is separated from the transmitting transducer by a distance (L). It receives the pulse and converts it into electrical energy. The propagation time (T) is measured, and the pulse velocity V is calculated with Equation (1) by dividing L by T:E is the dynamic modulus of elasticity, μ is the dynamic Poisson’s ratio, and ρ is the density . The pulV is the pulse velocity (m/s or mm/μs), L is the center-to-center distance of the sender/receiver surfaces (m or mm), and T is the propagation time (s or μs). Because concrete saturation affects the pulse rate, this factor must be considered when measuring the velocity. The pulse rate of saturated concrete can be as large as 5% and is less sensitive to changes in the relative quality of concrete.The accuracy of the measurement may vary depending on the tester’s ability to measure the propagation distance and the performance of the equipment. The strength of the received signal and the measured propagation time are affected by how well the transmitter and the receiver adhere to the concrete surface. The strength of the received signal is affected by the movement distance of the pulse between the transmitter and the receiver and the degree of cracking or deterioration of the concrete.The pulse velocity inside iron reaches twice the velocity in concrete, so when the pulse velocity is measured near reinforcement, the ultrasonic propagation velocity may be greater than that in unsupported concrete of the same composition. Therefore, measurements near reinforcing bars parallel to the direction of propagation of the pulses should be avoided where possible . Lastly,Sutan and Meganathan obtained UPV values by indirect penetration through one side of the concrete. Using this, we evaluated the accuracy of defect detection and depth measurement with a relational expression for calculating the depth of a void. The presence of the defect could be confirmed 100% of the time, but it showed accuracy in the range of 60–99% in evaluating the depth of the defect. Equation (3) below is a relational expression applied to check the depth of a void H, and S is the pulse velocity in sound concrete, VC is the pulse velocity in defect concrete, and D is the distance at which the change of slope occurs. Although this method can detect the presence of cracks, the accuracy of the measured depth is poor.VThe relational expression for evaluating the depth of the crack formed in the vertical direction from the surface studied by Leslie et al. can be derived as follows. In order to determine the depth of a crack, a transmitter and a receiver are placed on both sides at the same distance from the crack. When an ultrasonic wave arrives at the tip of a crack, the wave is diffracted and propagated as a spherical wave, arriving at the receiver placed on the opposite side.  Since thC) of the ultrasonic wave is given by the following equation:S of the ultrasonic wave in the area where cracks do not exist is given by Equation (5) below. The depth of crack (H) can be obtained with Equation (6). This method of evaluating the depth of cracks is known as the TC-TS method [The arrival time (TS method .(5)TS=DC-TS method is not accurate [Equation (6) assumes that the speeds of ultrasonic waves in a concrete surface and inside are the same, but in reality, the speed of a surface wave and that of an internal wave in concrete are different, so the Taccurate . Since iWhen cracks growing in the thickness direction exist on a concrete surface, a simulation can be performed to determine whether the crack detection and depth could be quantified using the UPV of one surface. For this, a concrete block with different crack depths was modeled by Onscale  which is a cloud engineering simulation platform, and the easiness of UPV inspection using two different frequencies was compared. Theoretically, the ultrasonic time-of-flight (TOF) increases proportionally as the distance between the transducers  increases when there are no cracks and increases as the ultrasonic wave travels through the cracks.After modeling a 2D-shaped concrete block, the general physical properties of the concrete block see  were inpThe physical shape of the concrete block model was simulated in 2D as 600 mm (length) × 150 mm (height). The models were composed of three types. The first and second ones had vertical cracks of 70 mm and 45 mm in the center of the block, respectively, and the other had no cracks. The three shapes of concrete blocks are shown in ASTM C597 requires that a transmitter with a resonant frequency in the range of 20 to 100 kHz be used for an ultrasonic propagation speed test in concrete. Therefore, the ultrasonic frequency for the main simulation was selected as an approximately intermediate value of 65 kHz. In order to confirm the effect of the difference in the distance between the crack and the transducer on evaluating the depth of the crack, the ultrasonic pulse speed was measured by varying the distance between the transmitter and the crack for each depth of the crack.As shown in The propagation time (TOF) of the ultrasonic pulse was measured based on the first peak point of the pulse that appeared when the pulse reached the receiver, as shown in The TOF change with the difference in the distance between the transducer and the crack was compared under the condition of cracks of the same size. Cracks No. 1 and No. 3 are located at a distance of 270 mm from the transmitter, and No. 2 and No. 4 are located at a distance of 150 mm. In the section without cracks, TOF increased at a certain rate, but when passing through sections with cracks of 70 mm and 45 mm, TOF showed a larger value see . HoweverWith the crack in the center, the crack was evaluated using the TOF of each section by the examinee’s position under the condition where the distance before and after the crack was the same. For the speed of the uncracked part, the TOF of No. 5 was applied. For the cracked part, we used the TOF confirmed by the simulation of the corresponding model.As shown in The ultrasonic pulse rate is affected by factors such as the cement type , aggregaFor the experiment, as shown in The transmitter and the receiver were separated by a distance. The surface of the concrete block was marked at intervals of 60 mm so that a constant value could always be obtained when measuring the ultrasonic speed. A diagram of the experimental apparatus is shown in A measurement of the ultrasonic pulse propagation time on the concrete surface was performed with the same conditions as the simulation model. In a concrete block with 45 mm and 70 mm cracks, the transmitter was positioned at 150 mm and 270 mm away from the crack, and the propagation time (TOF) of the pulse was measured. The propagation time and speed of ultrasonic pulses were checked on the block surface up to a distance of 540 mm, the maximum range that can be measured at intervals of 60 mm. In order to improve the reproducibility and accuracy of the experimental results, the ultrasonic pulse propagation time was measured a total of five times for each condition, and the average value was used to apply the known relational expression to evaluate the depth of the crack.In experiments and simulations, the time of propagation (TOF) of ultrasonic pulses was determined by checking the first peak of the first cycle as in the previous experiments. . In ordeSince various materials such as aggregate and cement are mixed inside the concrete, the damping (scattering and absorption) is large. ASTM C597 requires using a resonant frequency in the range of 20 to 100 kHz, so it is easy to identify the first peak by selecting 65 kHz, which is within the frequency range required by ASTM C597. With 110 kHz, the resolution can be expected to be a little better in the simulation and experiment, so it was compared with 65 kHz. Signals using 65 kHz and 110 kHz are shown in As shown in The depth of a vertical crack was obtained when the TOF value measured experimentally was substituted into the relational expression from Sutan and from Leslie and Cheesman. The accuracy of the two relations was confirmed. In addition, only the test results of 65 kHz were used to evaluate the depth of cracks. In relation to Sutan and Meganathan, the crack evaluation was conducted with different transducer spacing as in the simulation, and the accuracy of the crack evaluation was confirmed.In the case of Experiment 1, as shown in When the relationship between Sutan and Meganathan was applied, it was confirmed that the accuracy increased as the distance between the transducers increased in both the experiment and the simulation with the 70 mm crack condition. However, since all the results were evaluated with a value smaller than the actual crack depth, it is expected that the accuracy can be improved if the probe is tested with a longer distance between the probes.In the case of experiment No. 1, as shown in Therefore, when the concrete surface for crack evaluation is wide, it is judged that the accuracy of crack-depth evaluation can be improved by varying the gap between the transmitter and the examiner to evaluate the crack depth in various ways. However, since this experiment evaluated only the accuracy of the crack depth with a single condition of 70 mm, the accuracy, when the crack depth was different, was unknown, so the conversion of the crack evaluation relational expression was not considered.In the 45 mm crack condition, there was no difference in TOF from the case without cracks, so the depth of the crack could be quantified only when using the TOF change values of the front and rear ends of the crack. However, the accuracy is at the level of 15.2 to 15.5%, which is judged to be a level at which only the presence or absence of cracks can be confirmed. When the relational expression for crack measurement was applied, using both simulation and experimental results, we could obtain closer evaluation results to the actual crack depth compared to the previous relational equations for crack evaluation.With the 70 mm crack condition, both the experiment and the simulation showed the same tendency for the depth of the crack to increase as the distance between the transducers increased. Through this, it was found that in the crack evaluation using Leslie and Cheesman’s equations, it would be possible to evaluate the depth of cracks more precisely after determining the optimal transducer spacing. In the 45 mm crack condition, the depth of the crack could be evaluated in the simulation when the relationship between Sutan and Meganathan was applied. The accuracy was very low at 15.2 to 15.5%.The next inspection target was a surface where cracks can be visually confirmed on the floor near a site where a concrete storage facility is located. The concrete surface where cracks were confirmed was a floor area near a concrete building, which had nothing to do with the soundness of the structure, but there was no difference in detecting and evaluating cracks using the UPV method. Therefore, crack detection and crack-depth evaluation using UPV were performed.The ultrasonic speed was measured a total of four times while the position of the examinee was spaced by 60 mm, and the transmitter was fixed in the same condition as the experimental conditions on the test piece . As the accuracy was confirmed by the experiment, the ultrasonic propagation time was measured with the crack at 150 mm from the transmitter. A diagram of the ultrasonic inspection of the bottom part where cracks were confirmed is shown in As shown in In the section where cracks exist (120→180 mm), the difference between the same section and the same section without cracks was large. The crack showed a TOF increase of 72.9 μs, similar to the 63.5-μs increase in TOF in the same section of Experiment 2 with similar conditions. On the other hand, in the area without cracks, the TOF increase showed a large difference of 16.4 μs, so the existence of cracks could be easily confirmed even with the TOF change. When inspecting the concrete floor surface, the TOF change greatly increased past the crack and showed a similar shape to that of the test with the 70 mm crack condition. Considering that the TOF change of the 45 mm crack in the experiment was insignificant, it was estimated that the crack in the floor was deeper than at least 45 mm.As shown in As shown in Finite element analysis and experiments were performed on non-cracked concrete blocks and 45 mm and 70 mm vertical cracks to estimate the crack depth in concrete using ultrasonic propagation time. As a result of measuring the time-of-flight change by changing the positions of the transmitter and receiver converters, it was confirmed that the finite element analysis results agree well with the experimental results. The depth of the defect was calculated using various formulas using the measured values, and the accuracy was compared to show a high degree of similarity to the theoretical value. It also shows the results of applying the verified UPV method to cracks found in the actual field.In this study, the theoretical crack length measurement method was verified through FEM(Finite Element Method) modeling and actual experiments. In addition, it was confirmed that the crack detection and depth evaluation method using ultrasonic pulse velocity in cracked concrete structures can be a very useful tool to maintain the soundness and safety of the structure.


Background:Staphylococcus aureus is the second-leading cause of late-onset sepsis among infants in US neonatal intensive care units (NICUs). Management of S. aureus bacteremia and meningitis in infants varies widely due to the lack of standardized guidelines. We examined the association between initial antibiotic duration and recurrent S. aureus infection or death among NICU infants with S. aureus bacteremia and/or meningitis. Methods: We conducted a retrospective cohort study of infants in Pediatrix Medical Group NICUs from 1997 to 2018 with first episode of S. aureus bacteremia and/or meningitis, identified as having at least 1 blood or cerebrospinal fluid (CSF) culture growing only S. aureus at any point during their NICU stay. Excluded infants were those not started on antistaphylococcal therapy within 2 days of positive culture, those with had endocarditis or osteomyelitis, or those who died or were discharged during or up to 1 day after antibiotic cessation. Antibiotic cessation was defined as last day of antibiotic given if followed by at least 3 days without antibiotics. Multivariable logistic regression was used to analyze the association between antibiotic duration categorized as <14 or ≥14 days) and recurrent SA infection , or death (within 7 days of antibiotic cessation and at discharge). Results: Of 4,086 infants included, 3,991 (98%) had S. aureus bacteremia only and 95 (2%) had meningitis ± bacteremia. Of those with bacteremia only, 2,017 (50.5%), and 17 (18%) of those with meningitis received <14 days antibiotics (Figure Conclusions: In the largest study thus far examining antibiotic duration among hospitalized infants with S. aureus bacteremia and/or meningitis, ≥14 days antibiotics was associated with decreased odds of recurrent infection or death. Further studies are needed to define the optimal treatment duration and identify clinical factors distinguishing infants able to safely receive a shorter antibiotic duration.Funding: NoDisclosures: None


Deep sternal wound infection (DSWI) is a rare but serious complication after median sternotomy, and treatment success depends mainly on surgical experience. Traditional treatment methods for DSWI include complete debridement, vacuum sealing drainage wound therapy and sometimes transposition of muscle flap. This study aimed to evaluate the utility of antibiotic-loaded bone cement combined with vacuum sealing drainage on DSWI and explore the effect of this treatment on lung function.Between January 2018 and December 2019, we treated 12 patients suffering a mediastinitis and open thorax using antibiotic-loaded bone cement combined with vacuum sealing drainage. Subsequently, the blood and local concentration of antibiotic were measured. The patient characteristics, pulmonary function, were retrospectively analyzed. Subjects were followed up for 12 months.There were no intraoperative deaths. All patients’ healing wounds were first-stage healing without complications and reoperation, the mean hospital stay was 20.2 ± 3.5 days. Local vancomycin concentrations largely exceeded the ones needed for their efficacy while little antibiotic was found in the blood. Pulmonary function testing was improved 2 weeks after the operation. No infection reoccurred in12-month follow-up.The antibiotic-loaded bone cement combined with vacuum sealing drainage might be an effective method for the sternal reconstruction of deep sternal wound infection and it can improve the patient's lung function in a short time. Deep sternal wound infection (DSWI) following cardiac surgery is a devastating complication with the need for subsequent surgical procedures, prolonged hospital stay and increased morbidity and mortality –3. Its iConservative treatment methods for DSWI include repeated debridement, occlusive continuous irrigation, and vacuum-assisted closure , 8. HoweAntibiotic-loaded bone cement (ALBC) is introduced by Buchholz and Engelbrecht in 1970 . CurrentIn this review, we describes our method in treating DSWI after cardiac surgery combined ALBC with VSD and report the preliminary clinical results.The retrospective study was approved by the hospital ethics committee and informed consent of patients. From January 2018 to December 2019, 12 patients with DSWI following cardiac surgery underwent ALBC and VSD treatment in the department of cardiac surgery at affiliated Wuxi People's Hospital of Nanjing Medical University. In each case, after the diagnosis of DSWI was established, the basic principle of treatment were debridement, administration of culture-specific or broad-spectrum antibiotic. The patient characteristics, pathogenic data, the mean hospital stays were retrospectively analyzed  an organism is isolated from culture of mediastinal tissue or fluid; (II) evidence of mediastinitis seen during surgery; (III) one of the following conditions: chest pain, sternal instability, or fever (> 38 °C) in combination with either purulent discharge from the mediastinum or isolation of an organism from culture of blood or mediastinal drainage .We assembled a multidisciplinary team in our department that included cardiac surgeons, chronic wound control physician, Clinical pharmacists, dietitian and nurses.Complete debridement of the wound always took place in the operating room under general anesthesia. A thorough mediastinal wash out was the first step of sternal reconstruction. Next, Operative debridement of infected bone and soft tissue was used, including removal of sternal wires and other foreign bodies  . Then, nMethod 1. If infected sternal with minor bone loss Fig. ig. F. Tw. The ALBC was placed in between both sternal halves and covered the defect of sternal to fix the thorax , perioperative antibiotic choice, minimization of blood product usage, postoperative wound care, and patient education regarding prevention of incisional infection .Measurements of pulmonary function (n = 12) using volume displacement body plethysmography were carried out by comparing the results to preoperative reference value.The blood concentration of vancomycin (n = 9) was assayed at postoperative day 1, day 3, day 5, day 7, day 9, day 11, day 14 and local concentration was assayed at postoperative day 1, day 3, day 5, day 7.t-test was performed to evaluate the changes in pulmonary function values. A P value below 0.05 was considered statistically significant.Continuous variables were expressed as mean ± standard deviation. A paired P < 0.05) –(162 ± 36) μg/mL. The blood concentration of vancomycin after ALBC treatment was measured at far below its toxic concentration (60 mg/L) , use of bilateral internal thoracic artery . TreatmeIt is well known that sternal instability triggers mediastinitis and vice versa. So when dealing with DSWI, both the instability and infection must be treated, due to the severe systemic repercussions of both factors . DSWI coStaphylococcus aureus (MRSA), are the most common etiological factors for DSWI [creactive protein levels showed no signs of infection. In our opinion, the use of antibiotic-loaded bone cement and VSD, in association with a systemic therapy such as antibiotic therapy, nutritional support therapy, anti-coagulant therapy, are the keystone of treatment for DSWI.Patients with DSWI are typically treated with intravenous antibiotic agents for a few days based on the bacterial culture and drug sensitivity test. However, these systemic modes of administration often achieve only low local (target) drug concentrations due to tissue ischemia, resulting in a minimized local effect. This lack of effect could be due to relatively poor penetration of antibiotic into the bones , especiafor DSWI , 27. VanOwing to the obvious systemic toxicity by systemic administration, local application of vancomycin is increasingly being adopted to decrease the toxic side effects . HoweverThe prevalence of midline sternotomy as the most commonly used surgical approach in open heart surgery has resulted in post-sternotomy deep wound infections remaining a major challenge. The management of DSWI requires early and sufficient surgical debridement, combined with bactericidal antibiotic therapy. Herein, we described a DSWI protocol involving implantation of antibiotic-loaded bone cement combined with VSD because of its excellent mechanical properties and sustainable drug delivery. Future studies will be conducted to determine if this technique could be used as a treatment strategy for DSWI.Many questions, including what is the optimal antibiotic dose, What kind of patient would benefit from it and which is the optimal antibiotic-cement combination to eradicate microorganisms specifically, are still open. This is a retrospective case series presentation with no comparison group, the sample size is small, and the follow-up period is short. It remains to be seen whether there are related complications caused by ALBC in the long-term follow-up.


Clostridioides difficile. There is also evidence that the use of different chemical classes of antibiotics for the treatment of a variety of ailments can lead to several health issues including gastrointestinal, immunologic, and neurocognitive conditions. This review discusses gut dysbiosis, its symptoms and one important cause, which is antibiotic therapy for the induction of gut dysbiosis. Since the maintenance of good gut health is important for the well-being and functioning of physiological and cognitive activities through the normal gut-microbiota–brain relationship, the condition of dysbiosis is not desirable. Specific therapies are prescribed by medical practitioners for the cure of a variety of ailments, and, if the prescription of antibiotics becomes unavoidable, there is a possibility of the onset of gut dysbiosis as the side or after effects. Therefore, the restoration of imbalanced gut microbiota to its balanced condition becomes necessary. A healthy relationship between gut microbiota and the brain can be achieved with the introduction of probiotic strains into the gut in a practical and consumer-friendly way, such as consumption of food and beverages prepared with the use of characterised probiotic species, fermented foods as the potential biotics, or synbiotic supplements.Antibiotic therapy through short-term or repeated long-term prescriptions can have several damaging effects on the normal microbiota of the gastrointestinal tract. Changes in microbiota could be multiple including decreased diversity of species in gut microbiota, changed metabolic activity, and the occurrence of antibiotic-resistant strains. Antibiotic-induced gut dysbiosis in turn can induce antibiotic-associated diarrhoea and recurrent infections caused by  The contribution of the gut microbiota to human health has been established in that the normal gut microbiota provides protection against invasive microorganisms, which could be potential pathogens. The intestinal microbiota is a dynamic community of millions of microorganisms that play important roles in the sustainability of human health . Most ofs system ,4,5. Thes system .Nonetheless, therapy with the medication of antibiotics of a complex chemical nature can disrupt the microbial balance of the gut, which results in the development of antimicrobial resistance in pathogens and other diseases due to the after effects of chemotherapy. When the gut microbiota is interrupted and becomes out of balance, it can lead to dysbiosis. When the normal human microbiota in the gastrointestinal tract, including small and large intestines, are affected by harmful microbial species, a condition of dysbiosis typically occurs. This might occur through the disruption in colonisation resistance in a number of ways, such as direct or side effects on normal gut microbiota by the intake of medication, competition between pathogens and gut microbiota for the available nutrients in the gut, and eventually a decline in the host’s immune responses .The reason for the disturbance in healthy microbiota could be short- or long-term treatments with the oral consumption of antibiotics. In the general practice of chemotherapy, a large group of chemicals is used as antibiotics for the treatment of different types of infections developed in different organs and systems of patients. The clinical use of antibiotics has modernised the scope of medicine dealing with the treatment of various infectious diseases common in diverse communities in all countries. Nevertheless, their therapeutic actions are not limited to the disease-causing pathogens for which they are prescribed, and hence these chemicals generally also influence the sustainability of beneficial microbes present in the gut of patients. The commonly prescribed antibiotics belong to several classes based on their chemical structures, including beta-lactam antibiotics, aminoglycosides, daptomycin, fluoroquinolones, glycopeptides (teicoplanin and vancomycin) and linezolid.Antibiotics cannot perform their preferential action on pathogens specifically, but also act on all microorganisms including the normal microbiota present at that time in the gut of a patient. Such activity of antibiotics affects the constitution of normal gut microbiota. The course of antibiotic therapy adversely affects the diversity of the microbiota in the gastrointestinal tract. As a result, antibiotics interfere with host–microbes interactions, and immune system homeostasis, and impair colonisation resistance toward new pathogenic strains entering the host system. In fact, treatments using antibiotics for targeting infections can also impair the severity of other ailments, such as inflammatory bowel diseases and colitis through the disturbance of toll-like receptor signalling. As a result, variations in the diversity of gut microbiota occur, which in the longer term could be linked to a number of health conditions, including cardiovascular disease ,9, liverIn further sections, this review will discuss gut dysbiosis, its symptoms, types of antibiotics  causing dysbiosis, cognitive weakening with the changes in molecular level communication between gut microbiota and brain, and finally the restoration of gut-microbiota imbalance to eliminate the condition of dysbiosis.Candida yeast infection, diabetes, and skin conditions, such as eczema, etc. Antibiotic-induced gut dysbiosis in turn can induce diarrhoea and recurrent infections caused by Clostridioides difficile [The term dysbiosis has been described as the disruption of the symbiotic balance between microbiota and the host. Dysbiosis implies frequent changes and eventually leads to disturbances in the ecology of gut microbiota, which has been characterised as an adaptation in the composition and functioning of the microbiota. Dysbiosis can be caused by mainly two factors, which could be either environmental or host-related . The conifficile ,17,18.Before the actual diagnosis of a specific health condition, certain symptoms can initially indicate the actual occurrence of dysbiosis in a patient. The symptoms will be obvious and different depending on the location of the imbalance in the gut microbiota. Dysbiosis symptoms will also vary based on the type of gut bacteria affected. Common symptoms of dysbiosis include diarrhoea, bloating, bad breath , fatigue due to mal-absorption of nutrients by an upset digestion, constipation, nausea, chest pain, and vaginal or rectal itching, etc. . SymptomAntibiotics are major disruptors of gut microbiota . The oraDuring and after the long-term therapy with the prescription of different classes of antibiotics , the delIn a recent report published in 2022, 16S rRNA gene sequencing was used to evaluate the short- and long-term effects of four different commonly used antibiotics, including ampicillin, vancomycin, metronidazole and neomycin on the murine intestinal microbiota. The researchers found changes in the intestinal microbiota, which indicated the impact of antibiotics’ action. As a result, dysbiosis of the gut’s normal microbiota led to a struggle for their sustainability among different bacterial populations in the gut. The studies identified the consistent changes in the microbiota following chemotherapy with the use of quinolone and metronidazole compounds, and reported that the combination treatment with a mixture of antibiotics may even result in a long-term dysbiosis, compared with the treatment with one type of antibiotic .The role of gut microbiota has been identified and studied for its involvement in brain functions, including cognition, brain performance ,70, cognIt is interesting to know that resident microbial strains in the gut have an impact on the production of major neurotransmitters, such as dopamine, norepinephrine, also called noradrenaline, serotonin , histamiSignals are transported from the gastrointestinal tract (GIT) and its microbiota to the brain through the network of fibres of the afferent vagus nerve, linked to receptors in different parts of the digestive system, including oesophagus, liver and pancreas . After rThe disturbances in the GIT microbiota have been broadly associated with symptoms of major depression disorders, although the identity of causal microbial species and the underlying mechanisms are yet to be fully understood. The effects of short-term antibiotic-induced depletion or changes in the microbiota have been examined on cognitive function in mice. The work of Fröhlich et al. has been considered a basis for translational research into the role of gut microbiota in human cognition. The authors depicted a strong effect mediated by antibiotics on GIT microbiota composition. In this study, change in cognitive behaviour was found linked with the unusual levels of peripheral metabolites and functional changes in neural signalling pathways in the brain .Bacteroides species have been found to differentially modulate depression-like behaviour via gut–brain metabolic signalling. In a recent report of 2022, a team of researchers identified Bacteroides species that contributed to depression susceptibility in mice by metabolic regulation along the gut–brain axis. The report highlighted activity in three strains of Bacteroides, B. uniformis, B. fragilis, and B. caccae, which impaired the hippocampal neurogenesis. The hippocampal serotonin levels were found adversely affected by these species of Bacteroides [teroides .The administration of antibiotics can be a useful pharmacological tool to investigate the contributory relationships between fluctuations in gut microbiota, corresponding to brain function and cognitive behaviour. A molecular-level understanding of the depletion of GIT microbiota acutely or chronically was studied through the administration of a mixture of antibiotics at different stages of the lifecycle of animals. This information would be useful in allowing the dose of antibiotics and simulating the clinical condition in humans . A persiIn the case of cognitive impairment (confirmed in a test for the disruption of novel object recognition memory), the measure of antibiotic absorbed was found below the detection limit. The researchers concluded the cognitive impairment in antibiotic-treated mice must have resulted from gut dysbiosis rather than from a systemic response from the administration of an antibiotic. This report on studies performed on antibiotic-treated mice discussed several important aspects, such as—multiple antibiotic treatments cause dysbiosis and metabolite depletion in the gut; circulating metabolites may be messengers in the communication between gut dysbiosis and brain; antibiotic-induced dysbiosis impairs cognitive performance; cognitive impairment due to gut dysbiosis is associated with changes in the expression of tight-junction-proteins, brain-derived neurotrophic factor, and the serotonin transporter, etc. . Considering the fact that short-term broad-spectrum antibiotic treatment given orally intensely affects the phenotype and function of mucosal immune cell populations that occur by induction of inflammatory activation of colonic iNKT and T helper cells, then the implications of repeated broad-spectrum antibiotic use could be further critical and the cause of the breakdown of acceptance mechanisms between the normal microbiota resident in the gastrointestinal tract and the immune system of the host. Antibiotic treatment given to younger patients in their early years of life will lead to an increased risk of gut inflammatory conditions. Hence, the condition of dysbiosis needs to be rectified at its early detection to restore the important role of gut microbiota in the modulation of intestinal immunity. The intake of diet is an important resource and practical for correcting the bacterial imbalance in the gut, therefore the addition of pre-, pro-, and synbiotic food and beverages in nutrition can support keeping the gut microbiota in a balanced condition ,87. SeveDysbiosis could be repaired with the re-introduction of friendly microbial species in form of important probiotics in the gut. Consumption of food or beverages that contain live probiotic bacteria at the time of consumption would help in the correction of dysbiosis ,90. CharThe potential for the consumption of functional foods has also been explored to help in the remediation of certain psychological issues. Studies have reported that correction can be made in the composition of imbalanced gut microbiota. The biotherapy in the form of ingestion of bioactive components including prebiotics, postbiotics, and parabiotics in fermented foods can affect the intelligence, mood, autism, behaviour and psychology of its host through the gut–brain axis  94,95,9,995,96.Prebiotics and oligosaccharide-based fibres are selectively utilised as substrates available in the host’s gut system by probiotic strains to develop and sustain their population in the gut ,98. A heLactobacillus reuteri (current nomenclature—Limosilactobacillus reuteri), and the immune-modulatory effect of this probiotic strain have been investigated on an Epithelial Cell Line IPEC-J2 [Salmonella typhimurium, which infects both humans and animals. This pathogen most often causes gastroenteritis, provoking the condition of dysbiosis. The most relevant result of this in vitro study was a case of immunity modulation by the probiotic strain, where L. reuteri was found to be a factor in the stimulation of the innate immune-cell response. The response was exhibited by anti- and pro-inflammatory activities. The pretreatment of pathogen-bacterial cells with live Lactobacilli or their exopolysaccharide prior to infection showed a suppressive effect on the inflammatory response induced by Salmonella typhimurium [The exopolysaccharides secreted by  IPEC-J2 . Cell lihimurium .Information collected from the above-discussed research outcomes has proved that the onset of dysbiosis predominantly disturbs the balance of microbial diversity and their numbers in gut microbiota. One of the several causes of dysbiosis has been identified as the side or after effects of chemotherapy prescribing different classes of antibiotics. It is suggested that, after antibiotic treatment, the analysis of the diversity of gut microbiota and its differential abundance should be performed. It is recommended that studies investigating the effect of antibiotics on the gut microbiome should exclude those participants that have been subjected to antibiotic treatment within four months prior to collection and analysis of baseline samples. Additional examinations need to be made into the functional implications of antibiotic-induced dysbiosis in the gut microbiome.Antibiotics can induce long-lasting unfavourable effects on patients, compromising the diversity, composition and altered functions of the gut microbiota. The effectiveness of different clinical therapies also depends on the action of the gut microbiota due to its condition at the time of treatment. Different antibiotic treatments affect the ability of the gut microbiota to control intestinal inflammation, as it has been studied in cases where faecal microbiota was transplanted in an experimental colitis model, and in ex vivo experiments with human intestinal biopsies. Although some modification strategies to prevent antibiotic-induced dysbiosis have been explored, such as the simultaneous administration of probiotics during antibiotic therapy, or the transplant of autologous faecal microbiota after the course of antibiotic treatment, both approaches have not shown complete success in the restoration of healthy gut microbiota, particularly in cases of acute dysbiosis, or in weaker patients with low immunity ,108,109.The characterisation of microbiota should be supplemented by the exploration and analysis of the resistome, metagenome, and metabolome to provide more insight into the functional implications of antibiotic therapy on the microbiome. There is a relationship between the pharmacokinetic and pharmacodynamic of antibiotics and their clinical response. The action of chemotherapy includes efficacy as well as the toxicity of chemical molecules of drugs used as antibiotics. This relationship can be applied to define the therapeutic range of a particular class of antibiotic class for the purpose of therapeutic drug monitoring. The critical step is to define exposure to the doses prescribed and it is equally important to prescribe the correct class of antibiotic. Before the commencement of chemotherapy using an antibiotic, the infection-causing pathogens should be identified in clinical testing. Accordingly, a specific type of antibiotic or a broad-spectrum type should be prescribed to target the infections caused by Gram-positive or Gram-negative bacteria, or other microbial infections caused by fungal and yeast pathogens. This strategy of clinical practice can prevent the development of antibiotic resistance in pathogens being treated. Therapeutic drug monitoring should only be regarded as a means to achieve the main goal of providing safe and effective antibiotic therapy for all types of infections .In the last few decades, there has been a rise in the number of studies on gut microbiota , and the


Background: Improving antibiotic use is a key strategy to combat antimicrobial resistance. Here, we have described national outpatient antibiotic prescribing trends during the COVID-19 pandemic. We compared the monthly numbers of prescriptions in 2020–2021 to those from 2019 to describe the impact of the pandemic and to highlight areas for improvement. Methods: We used the IQVIA National Prescription Audit (NPA) data set to identify all antibiotic prescriptions dispensed from US retail pharmacies during January 2019–October 2021. We calculated the percentage change in volume of prescriptions for each month during the pandemic (beginning in March 2020) compared to the baseline (defined as the corresponding month in 2019). Data were characterized by patient age group  and antibiotic class and drug, including azithromycin. Results: Antibiotic prescriptions were lower than baseline during March 2020–June 2021. The greatest decrease in antibiotic prescribing volume occurred in May 2020 (40.0% lower than May 2019) . However, outpatient antibiotic prescribing levels in general, and azithromycin prescribing in particular, approached or exceeded prepandemic levels in July and August 2021. Ongoing surveillance and sustained outpatient antibiotic stewardship efforts are needed to optimize antibiotic use during the COVID-19 pandemic and beyond.Funding: NoneDisclosures: None