Suspension Rates Research Articles

Referral Rates for School Threat Assessment

ABSTRACTAlthough behavioral threat assessment and management (often shortened to “threat assessment”) has become widely used in US schools, no studies have systematically examined how frequently schools conduct threat assessments and how threat assessment rates vary as a function of student and school demographics. Of particular concern is that students with disabilities receive threat assessments at disproportionately high rates. This study examined the 1‐year frequency of threat assessments in a statewide sample of 611 elementary, 341 middle, and 269 high schools reporting 15,301 threat assessments, of which 41% concerned students with disabilities. We identified threat assessment rate differences associated with student grade, gender, race/ethnicity, and disability status. We further examined the association between threat assessment rates and school‐level demographic characteristics including racial/ethnic composition, prevalence of economically disadvantaged students, and proportion of students with a disability. To place these results in context, we compared findings for threat assessment with out‐of‐school suspension rates. We discuss reasons why students with disabilities might be referred for BTAM at a high rate and recommend practices for assuring their educational rights and needs are safeguarded. Evolving school threat assessment policies should recognize the practice demands placed on school staff to evaluate a substantial number of students.

Role of vegetable oil as UV light protector for Beauveria bassiana and Metarhizium anisopliae in management of Bactrocera zonata

Entomopathogenic fungi (EPF), Metarhizium anisopliae and Beauveria bassiana, are used in the field against different insect pests because they are best candidates to include in integrated pest management. But the efficacy of these EPF is limited in the field conditions because different environmental conditions like; sunlight, UV light, visible light, temperature and humidity affects the conidial viability, shelf life and pathogenicity of EPF. The solution to this problem is the use of vegetable oils as liquid carriers to coat and shield the conidia. In the present study three different oils were used like, Sesame oil, sunflower oil and corn oil. The conidia of M. anisopliae and B. bassiana were exposed to three different intervals of UV light 15, 30 and 45 minutes. Conidia exposed to UV light after the addition of oil and making oil water emulsion with fungus. The germination percentage and pathogenicity of M. anisopliae and B. bassiana against adult and pupae (through immersion method) of Bactrocera zonata were recorded after exposure to UV light. Sesame oil showed highest conidia germination, adult mortality for M. anisopliae and B. bassiana after UV light exposure. In case of M. anisopliae germination rate reached up to 79.5% (48–51 h) and mortality 84.4% (7th day), lower rates in aqueous suspensions (germination: 43.3%; mortality: 35.6%). In case of B. bassiana germination rate reached up to 69.17% (48–51 h) and mortality 64.4% (7th day), lower rates in aqueous suspensions (germination: 33.3%; mortality: 35.6%). Adult emergence was highest in the aqueous suspensions and lowest in the sesame oil based formulation. Overall, M. anisopliae performed better than B. bassiana with sesame oil recommended to protect conidia from UV radiation.

Hydroxyl Functionalization of a Titanium Implant Drug Carrier Channel Modified by Vacuum Drying-Assisted Laser Texturing to Achieve Delayed Release of CIP-PLGA Microsphere Suspension.

Titanium alloys are commonly used for bone grafting, but in mandibular defect repair, implantation possibly fails due to bacterial infection. The establishment of a long-acting drug delivery system through microspheres and titanium channels can reduce the risk of infection. However, there is insufficient research on the mechanism of microsphere attachment and microsphere-liquid two-phase flow in the hydroxyl-functionalized titanium implantation channel modified by a vacuum-drying-assisted laser texturing. In this paper, poly(lactic-co-glycolic acid) (PLGA) loaded with ciprofloxacin (CIP) was attached to the titanium channel by vacuum drying-assisted laser texturing. Titanium macroscopic flow channels and microscopic texture morphology were designed; three mathematical models of titanium substrate-microsphere-droplet interactions were developed, and the hydroxyl-based surface functionalization mechanism and the effect of laser texture parameters on microsphere adhesion and microsphere-liquid two-phase flow on titanium channels were investigated. The results showed that vacuum drying-assisted laser texture can control the bonding degree of the PLGA hydroxyl group to the titanium channel, which affects the adhesion of microspheres. The laser texture modification can control the flow rate of the microsphere suspension in the titanium channel to achieve a dynamic adjustment of the release effect. The CIP-PLGA microsphere drug delivery system, based on vacuum drying-assisted laser texturing, enables sustained local drug release, providing a potential strategy to suppress inflammation around the implant and reduce the risk of postoperative infection.

The School-to-Prison Pipeline: Long-Run Impacts of School Suspensions on Adult Crime

Schools must balance student behavior management with the potential negatives of strict discipline. These policies can deter misbehavior but may stigmatize students and expose them to the criminal justice system early. We assess the impact of attending a strict discipline school on achievement, educational attainment, and adult criminal activity. Using data from a boundary change and principal switches, we find that higher suspension rates have significant negative long-term effects. Students at such schools are 15–20 percent more likely to be arrested and incarcerated as adults. Negative impacts on educational attainment are particularly pronounced for males and students of color. (JEL H75, I21, I28, J15, K42)

Association Between Multisystem Immune-related Adverse Events and Progression-free Survivals in PD-1/PD-L1 Inhibitor Monotherapy.

Immune-related adverse events (irAEs) occur in various organs, and sometimes multiply following treatment with immune checkpoint inhibitors (ICIs). This study aimed to determine the association between the number of irAEs and clinical outcomes. This was a retrospective study that included patients with lung cancer, melanoma, and head and neck cancer who were treated with anti-programmed cell death (ligand) 1 (PD-1/PD-L1) monotherapy. We evaluated the association between the number of irAEs and progression-free survival (PFS) in the simple Cox regression analysis. To eliminate the immortal-time bias, an additional landmark analysis was performed. In total, 92, 69, and 37 patients were allocated to the no, single, and multisystem irAEs groups, respectively. The multisystem irAEs were associated with better PFS compared to the no irAE group. In contrast, at the 12-week landmark, multisystem irAEs were associated with poor PFS compared to the no irAEs group. Furthermore, the rate of treatment suspension owing to irAEs in the multisystem irAEs group (62.5%) was higher than that in the single irAE group (17.3%) at the 12-week landmark. The incidence of multisystem irAEs was associated with improved clinical outcomes in patients with lung cancer, melanoma, and head and neck cancer treated with PD-1/PD-L1 inhibitor monotherapy. However, these results may be influenced by a potential immortal-time bias. When accounting for this bias, the early development of multisystem irAEs within 12 weeks was linked to treatment suspension and poorer clinical outcomes.

Do children receiving care and support have higher rates of school exclusion than their peers?

The Children, Young People and Education Committee recently held an inquiry to scrutinise the Welsh Government’s progress in delivering its Programme for Government Commitment to ‘explore radical reform of current services for children looked after and care leavers’. A key observation highlighted in their report was that there was a lack of robust data collected about various aspects of the care system. Notably it was highlighted that there is a lack of data collected about permanent exclusions and suspensions from school amongst children looked after in out of home care (CLA). This study was therefore designed to fill this evidence gap. Using anonymised linked administrative data held in SAIL Databank to identify those receiving care and support (CRCS) from their local authority, rates of permanent exclusion and suspension have been determined for the different groups within the CRCS cohort (CLA, those on the child protection register (CPR) and those receiving support who are neither CLA nor CPR) which have then been compared to their peers without this experience. Factors such as phase of education, setting, free school meal entitlement, having additional learning needs, age and gender have also been considered along with the reason for the suspension or exclusion. In drawing comparisons with peers, an intersectional approach was adopted to identify disparity. It is hoped that findings from this student study will stimulate debate and contribute towards the development of changes in Welsh policy.

Transport and retention mechanisms of highly suspended biochar in aquifer media

Biochar-based in-situ reaction zones are promising methods for groundwater remediation. However, the transport and retention of biochar in aquifer media remain unclear. Herein, biochar with high suspensibility was developed through nitrogen doping. A linear regression was used to analyze the relationship between particle size, concentration, time, and suspension rate. Seepage column experiments were conducted to investigate the transport and retention mechanisms of biochar in the aquifer medium. The ratio of biochar particle size (dp) to medium particle size (Dp) affected the permeability coefficient. At a 3.0 g/L injected concentration, hydraulic conductivity decreased within 3.3 × 10−3 ≤ dp/Dp ≤ 8.4 × 10−3. Within 9.7 × 10−3 ≤ dp/Dp ≤ 1.9 × 10−2, hydraulic conductivity first increased and then decreased. Within 2.5 × 10−2 ≤ dp/Dp ≤ 5.7 × 10−2, hydraulic conductivity slightly increased and then stabilized. This study confirms that nitrogen-doped biochar is an excellent remediation material for in-situ reaction zone.

Outcomes of uterosacral ligaments suspension for uterovaginal prolapse native-tissue repair: Over 1000-patient single-center study

Introduction and hypothesisSurgical repair is the mainstay of genital prolapse management. Among native-tissue apical procedures, high uterosacral ligaments suspension is considered a valid and effective option for central compartment repair. In this study, we aimed to evaluate the effectiveness, complications rate, and functional results of high USL suspension as a primary prolapse repair technique in a large cohort of patients. MethodsPatients who underwent vaginal hysterectomy followed by high uterosacral ligaments suspension for POP between January 2008 and December 2020 were retrospectively analyzed. Questionnaires and clinical interviews were preoperatively performed to assess symptoms and severity of urinary, bowel, and sexual dysfunctions. After surgical procedure, diagnostic cystoscopy was performed to evaluate ureteral patency. Postoperative data, objective, and subjective cure rate were then noted at the follow-up evaluation. ResultsA total of 1099 patients underwent high uterosacral ligaments suspension. The total complication rate was 3.4 % and recurrence in any of the vaginal compartments was 12.4 %. Reoperation for symptomatic prolapse recurrence or pessary treatment was required in 9 women (0.9 %). In the evaluation of postoperative questionnaires, functional outcomes analysis revealed a significant improvement (p < 0.05) in terms of stress urinary incontinence, urge urinary incontinence, voiding symptoms, constipation, and dyspareunia after prolapse repair. ConclusionUterosacral ligament suspension is a safe and effective procedure for primary surgical treatment of pelvic organ prolapse. Anatomical, functional, and subjective outcomes were very satisfactory, and the reoperation rate for recurrence was below 1%.

Universal Free School Meals and School and Student Outcomes

The White House National Strategy on Hunger, Nutrition, and Health included expanding free school meals to all students, regardless of income, which has sparked debate in the United States. To assess the association between universal free school meals (UFSMs) and school and student outcomes in the United States. An expert panel-informed protocol was developed to evaluate intervention or cohort studies comparing UFSM programs, such as the Community Eligibility Provision (CEP), with non-UFSM programs in US schools from August 2012 (excluding 2020-2021 due to the COVID-19 pandemic) in peer-reviewed publications or government reports. Outcomes included meal participation rates, attendance, dietary intake and quality, food waste, economic impact, food insecurity, anthropometrics, disciplinary actions, stigma, and shaming. A search of Medline, Econlit, Business Source Ultimate, ERIC, Agricola, Cab Abstracts, and CINAHL was performed in April 2024. Two researchers screened articles for inclusion, extracted data, and assessed risk of bias, using the Risk of Bias in Nonrandomized Studies of Interventions tool, for each included study. Grading of Recommendations, Assessment, Development, and Evaluations was used to assess the certainty of evidence for each outcome. The search identified 2784 records, with 6 studies included, representing more than 11 000 elementary, middle, and high schools. Nonrandomized intervention studies performed difference-in-difference or rate ratio analysis to investigate CEP participation rates, attendance, anthropometrics, and/or suspensions. CEP was associated with increased lunch (3 studies; moderate certainty) and breakfast (1 study; very low certainty) participation. School attendance was unchanged or improved in schools with CEP compared with schools without UFSM (2 studies; low certainty). CEP was associated with lower obesity prevalence (1 study; very low certainty) and fewer suspensions (1 study; very low certainty). Reasons for downgrading the certainty ratings included indirectness (data not fully representative of the United States) and inconsistency (small number of studies limiting ability to assess consistency). Despite the limitations, the evidence reflected well-designed longitudinal intervention studies appropriate for decision-making. In this systematic review, UFSMs were associated with increased meal participation, no or slight improvements in attendance, and decreased obesity prevalence and suspension rates; certainty of evidence was moderate for lunch participation and low or very low for other outcomes. Studies did not report several important outcomes, such as diet quality and food security, suggesting the need for more high-quality research encompassing policy-relevant indicators.

What features of education policies are effective in facilitating successful outcomes for Australian Department of Education students in out of home care?

AbstractAustralian and international research has consistently revealed that children residing in Out of Home Care (OOHC) experience low academic achievement, high rates of suspension, high rates of early school drop‐out and poor representation in post school study. To address the issues experienced by many students in OOHC, trauma informed policies have been introduced in schools and education districts, both in Australia and internationally. Informed by current research and by the Trauma Informed Approach Guidelines, developed by the US Department of Health and Human Services Substance Abuse and Mental Health Services Administration (SAMHSA), this research aimed to identify and analyse current OOHC education policies and support documents implemented by Australian State and Territory Departments of Education. Using a thematic content analysis of national and international research on the concerning educational outcomes of OOHC students, a policy analysis framework was created and used as the tool to analyse Australian OOHC education policies currently implemented by state and territory Departments of Education. Considerable variations were evident in OOHC education policies throughout Australian Departments of Education, with only the states of Queensland, New South Wales and Victoria having policies explicitly for OOHC students. Significant variations also existed in the levels and types of support provided between Australian states and territories. Australian Departments of Education, schools and teacher practitioners can do more to further enhance the educational experience of students residing in OOHC. Suggestions have been made on how this can be achieved.

What makes restorative justice equitable? “It’s a practice, not a program.”

PurposeThis study facilitated restorative coordinators in co-constructing and proposing solutions to common problems in RJ implementation.Design/methodology/approachThis study used grounded theory to examine barriers to equitable restorative justice (RJ) implementation in the US. Drawing on interviews and focus groups with restorative coordinators, we used a combination of inductive and deductive coding consistent with the grounded theory approach.FindingsCoordinators distinguished between RJ as a top-down, isolated “program” versus RJ as a collaborative “practice” among all stakeholders. Only the latter was equitable, in their view, and required a consistent principal commitment to building and maintaining an inclusive school culture. Participants recommended that teacher and principal preparation provide opportunities to cultivate critical consciousness and participate in RJ practices.Originality/valueExisting research on discipline reform tends to focus on outcomes, such as suspension rates. Instead, participants focused on the reform process, viewing equitable RJ as an ongoing “practice” to improve school culture. Our findings also open new discussions about leadership preparation content and pedagogy: participants called for preparation programs to cultivate critical consciousness and facility with RJ. Lastly, the study’s recruitment and focus group design raise important considerations for future RJ research.

Associations among educators' beliefs, intervention fidelity, and student outcomes in school-wide positive behavior interventions, and supports: A school-level moderated mediation analysis.

Existing literature has established the effectiveness of school-wide positive behavioral interventions and supports (SWPBIS) for improving school-level student behavioral and academic outcomes. Implementation of SWPBIS in uncontrolled settings is often suboptimal, leading to lackluster outcomes. Researchers have developed and validated several implementation strategies to improve individual-level implementation determinants (e.g., educators' supportive beliefs) to promote the successful delivery of universal programs (e.g., SWPBIS). However, empirical studies are needed to explore the mechanisms of change through which school-level educators' beliefs influence their delivery of SWPBIS. This school-level quasi-experimental study tested a mediational mechanism of change where changes in educators' beliefs work through their intervention fidelity of SWPBIS to influence student outcomes. We delivered the Supportive Belief Intervention (a school-wide implementation strategy used before training to promote educators' supportive beliefs about SWPBIS) and then Tier 1 SWPBIS training to 81 elementary schools serving diverse student populations. At the start of the academic year, school-level educators' beliefs were assessed before the Supportive Belief Intervention. At the end of the academic year, educators' beliefs, intervention fidelity, and rates of student reading proficiency and suspension were assessed. Conditional process analyses with nonparametric bootstrapping (mediational and first stage moderated mediational models) revealed that, at the school level, a larger increase in educators' supportive beliefs was associated with enhanced SWPBIS fidelity and better corollary student outcomes (increased reading proficiency and reduced suspension), while student socioeconomic status moderated the size of the mediation effect. Implications for research and practices about the implementation of SWPBIS and school context were discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Vaginal Cuff Self-Suspension Technique: A Novel Apical Suspension Technique for Patients With Uterovaginal Prolapse and Poor Tissue Integrity [ID 2683606

INTRODUCTION: Of all surgical approaches to correct apical prolapse, transvaginal native tissue repair (TNTR) accounts for 80–90% of cases. Conditions such as uncontrolled diabetes lead to poor tissue integrity, often rendering the anatomical structures necessary insufficient, resulting in recurrent prolapse or immediate procedure failure. We present a novel TNTR technique, called “vaginal cuff self-suspension technique” (VCST) that can be used in such cases to provide a potentially more reliable and efficient means of apical suspension. METHODS: We conducted a prospective observational study from July 2022 to July 2023 and followed all patients who underwent a total hysterectomy and subsequent TNTR for advanced uterovaginal prolapse and concurrent stage IV endometriosis or uncontrolled diabetes. Advanced uterovaginal prolapse was defined as either a POP-Q score of 3 or 4 or Baden-Walker Grade 3 or 4. Patients receiving VCST were compared with matched controls receiving other TNTR methods. The primary outcomes were recurrent apical prolapse at 6 months or failure at initial surgery, as discrete events. All appropriate IRB approvals were obtained. RESULTS: The study included 88 patients with 33 receiving VCST and 55 controls. Of the 55 controls, 42 utilized uterosacral ligament suspensions (USLS) and 13 utilized sacrospinous ligament fixations. Demographic factors were not significantly different. Patients receiving VCST had lower rates of initial failed suspension (6% versus 23%; P=.002) as well as a 37% decreased risk in confounder-adjusted models (risk ratio [RR] 0.63; 95% CI, 0.36–0.81; P=.003). Among patients with poorly controlled diabetes, the VCST had lower rates of recurrent prolapse (9% versus 47%) and a 81% decreased risk in confounder-adjusted models (RR 0.19; 95% CI, 0.08–0.31; P&lt;.001). CONCLUSION: Vaginal cuff self-suspension technique offers a simple and effective way to potentially prevent recurrent apical prolapse and/or immediate procedure failure for patients with advanced uterovaginal prolapse and concurrent stage IV endometriosis or poorly controlled diabetes.

Driver’s Licensure and Driving Outcomes Among Youths With Mood Disorders

Mood disorders are prevalent among adolescents and young adults, and their onset often coincides with driving eligibility. The understanding of how mood disorders are associated with youth driving outcomes is limited. To examine the association between the presence of a mood disorder and rates of licensing, crashes, violations, and suspensions among adolescents and young adults. This cohort study was conducted among New Jersey residents who were born 1987 to 2000, age eligible to acquire a driver's license from 2004 to 2017, and patients of the Children's Hospital of Philadelphia network within 2 years of licensure eligibility at age 17 years. The presence of a current (ie, ≤2 years of driving eligibility) mood disorder was identified using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) or International Statistical Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) codes. Rates of licensure and driving outcomes among youths who were licensed were compared among 1879 youths with and 84 294 youths without a current mood disorder from 2004 to 2017. Data were analyzed from June 2022 to July 2023. Acquisition of a driver's license and first involvement as a driver in a police-reported crash and rates of other adverse driving outcomes were assessed. Survival analysis was used to estimate adjusted hazard ratios (aHRs) for licensing and driving outcomes. Adjusted rate ratios (aRRs) were estimated for driving outcomes 12 and 48 months after licensure. Among 86 173 youths (median [IQR] age at the end of the study, 22.8 [19.7-26.5] years; 42 894 female [49.8%]), there were 1879 youths with and 84 294 youths without a mood disorder. A greater proportion of youths with mood disorders were female (1226 female [65.2%]) compared with those without mood disorders (41 668 female [49.4%]). At 48 months after licensure eligibility, 75.5% (95% CI, 73.3%-77.7%) and 83.8% (95% CI, 83.5%-84.1%) of youths with and without mood disorders, respectively, had acquired a license. Youths with mood disorders were 30% less likely to acquire a license than those without a mood disorder (aHR, 0.70 [95% CI, 0.66-0.74]). Licensed youths with mood disorders had higher overall crash rates than those without mood disorders over the first 48 months of driving (137.8 vs 104.8 crashes per 10 000 driver-months; aRR, 1.19 [95% CI, 1.08-1.31]); licensed youths with mood disorders also had higher rates of moving violations (aRR, 1.25 [95% CI, 1.13-1.38]) and license suspensions (aRR, 1.95 [95% CI, 1.53-2.49]). This study found that youths with mood disorders were less likely to be licensed and had higher rates of adverse driving outcomes than youths without mood disorders. These findings suggest that opportunities may exist to enhance driving mobility in this population and elucidate the mechanisms by which mood disorders are associated with crash risk.

Restoring Equity for Black Youth in Urban Schools: A Scoping Review

Zero tolerance policies in urban schools increased the disparities in urban school discipline for Black youth in comparison to white youth. Restorative interventions continue to be a popular response to deviant student behaviors; however, exploring the impact of restorative interventions in reducing harsh discipline on Black youth should be a continued focal point for scholars. This study used a scoping review to explore the breadth of knowledge available regarding using restorative interventions in urban schools. Five databases were used to identify relevant literature. Seven pieces of literature met the criteria for inclusion in this review. Findings revealed that restorative interventions do not have substantially positive impact on Black youth’s suspension rates; yet racial inequities in school and perceived negative thoughts about Black youth are among chief reasons Black youth are more likely suspended. Implications for future research and interventions are discussed.

Risk Factors Associated with Adverse Events Leading to Methotrexate Withdrawal in Elderly Rheumatoid Arthritis Patients: A Retrospective Cohort Study.

Background: Rheumatoid arthritis (RA) in elderly population represents a challenge for physicians in terms of therapeutic management. Methotrexate (MTX) is the first-line treatment among conventional synthetic-disease-modifying anti-rheumatic drugs (cs-DMARDs); however, it is often associated with adverse events (AEs). Therefore, the objective of this study was to identify the incidence and risk factors of MTX discontinuation due to AEs in elderly patients with RA in a long-term retrospective cohort study. Methods: Clinical sheets from elderly RA patients taking MTX from an outpatient rheumatology consult in a university centre were reviewed. To assess MTX persistence, we used Kaplan-Meir curves and Cox regression models to identify the risk of withdrawing MTX due to adverse events. Results: In total, 198 elderly RA patients who reported using MTX were included. Of them, the rates of definitive suspension of MTX due to AEs were 23.0% at 5 years, 35.6% at 10 years and 51.7% at 15 years. The main organs and system involved were gastrointestinal (15.7%) and mucocutaneous (3.0%). Factors associated with withdrawing MTX due to AEs were MTX dose ≥ 15 mg/wk (adjusted HR: 2.46, 95% CI: 1.22-4.96, p = 0.012); instead, the folic acid supplementation was protective for withdrawal (adjusted HR: 0.28, 95% CI: 0.16-0.49, p < 0.001). Conclusions: Higher doses of MTX increase the risk of withdrawals in elderly RA, while folic acid supplementation reduces the risk. Therefore, physicians working in therapeutic management for elderly patients using MTX must focus on using lower MTX doses together with the concomitant prescription of folic acid.

3D Printable Poly(N-isopropylacrylamide) Microgel Suspensions with Temperature-Dependent Rheological Responses.

Microgel suspensions have garnered significant interest in fundamental research due to their phase transition between liquid-like to paste-like behaviors stemming from tunable interparticle and particle-solvent interactions. Particularly, stimuli-responsive microgels undergo faster volume changes in response to external stimuli in comparison to their bulk counterparts, while maintaining their structural integrity. Here, concentrated and diluted suspensions of poly(N-isopropylacrylamide) (PNIPAm) microgels are dispersed to different packing fractions in water for the characterizations of temperature-responsive rheological responses. In the intrinsic volume phase transition (VPT), polymer chains collapse, and microgels shrink to smaller sizes. Additionally, the intermicrogel and microgel-solvent interactions vary in VPT, which results in microgel clusters that significantly affect the linear shear moduli of suspensions. The effect of the temperature ramp rate of PNIPAm microgel suspensions on rheological responses is characterized. Moreover, the effect of the mass fraction of microgels on the relative viscosity of dilute microgel suspensions is investigated. These results shed light on understanding the heating and cooling rate-dependent temperature responsiveness of PNIPAm microgel suspensions, establishing pathways to regulate the rheological characteristics in temperature-responsive microgel-based platforms. Therefore, this work envisions technological advancements in different fields such as drug delivery, tissue engineering, and diagnostic tools.

The impact of barrier arrangements on the transmission of respiratory infectious diseases in nursing homes in Hong Kong

Respiratory infectious diseases have affected the health of the elderly. This study investigated the optimization of physical barriers as a low-cost design strategy to reduce the risk of infection in nursing homes for the elderly in Hong Kong, which were significantly affected by the outbreak of COVID-19. First, data on two types of rooms, single and multi-occupancy, were collected from a field investigation of typical local nursing homes. Subsequently, Computational Fluid Dynamics (CFD) simulations were employed to analyse the effects of various barrier heights on the propagation, suspension, deposition and elimination of aerosol particles in these room types, thereby evaluating infection risks. The findings reveal that in single-occupancy rooms, a barrier height of 2.1 m is effective in curtailing the spread of the virus over distances. Conversely, in multi-occupancy rooms, while a 1.8-m barrier is necessary, the rate of particle suspension is considerably higher, necessitating additional ventilation measures. Based on these findings, the study provides quantitative criteria for the implementation of physical barriers as a low-cost physical measure in nursing homes and provides recommendations for the effective prevention of respiratory infectious diseases through design modifications.

Evaluation of Okra Pectin from Different Genotypes as Effective Suspending Agents in Pharmaceutical Formulations

Introduction: Natural suspending agents are increasingly being investigated because of their relative non-toxicity, lesser cost, availability and biocompatibility compared to the currently utilised synthetic and semi-synthetic suspending agents. Pectin, a biopolymer found naturally in plants is gaining increased application in the pharmaceutical and biotechnology industry following its successful functional application as gelling agents, emulsifying agents and fat substitutes in the food industry. This study aimed at evaluating the suspending properties of pectin obtained from five okra (Abelmoschus esculentus L.) genotypes; PL1 (Penkrumah), PL2 (Agbagoma), PL3 (Asha), PL4 (Sengavi) and PL5 (Balabi). Materials and methods: The pectin was extracted using standard protocols and characterised by investigating properties such as degree of esterification. A 5% w/v paracetamol suspension was formulated utilising okra pectin as a suspending agent at concentrations of 0.5%, 1% and 2%w/v and compared to Tragacanth gum suspensions at the same concentrations (0.5%, 1% and 2%w/v). Results: All the extracted pectins had low degrees of esterification (?50 %). The pH, redispersibility, apparent viscosity, sedimentation rate and sedimentation volume of the formulated suspensions were investigated over a 4-week period. The suspensions were stable as evidenced by no significant (p?0.05) fluctuations in pH during the period of study. Compared to when tragacanth was used as a suspending agent, the sedimentation rates, the flow rates of suspensions and redispersibility of the paracetamol suspensions utilising okra pectin were lower while the sedimentation volumes were higher at all the concentrations utilized and met standard requirements. Conclusion: The evidence suggests that all five okra genotypes exhibit better suspending properties when compared to tragacanth gum and thus may be used as an alternative suspending agent.

Understanding of the flocculating performance in varying salinity solutions of Chi-g-CPAM and CPAM

In this work, the adsorption performance of a novel chitosan-based flocculant (Chi-g-CPAM) and a cationic flocculant (CPAM) onto the kaolinite surface as well as the interaction mechanisms have been investigated by settling tests, atomic force microscopy (AFM) and quartz crystal microbalance with dissipation (QCM-D). When the KCl concentration of the solution altered from 1 mM to 100 mM, the settling rate of kaolinite suspension using CPAM deteriorated from 2.73 m/h to 1.97 m/h. However, the Chi-g-CPAM exhibited salt resistance as the settling rate changed slightly from 2.34 m/h to 2.44 m/h. From the QCM-D results, the Δf of CPAM onto silica sensor changed from − 3.6 Hz to − 33.6 Hz and -ΔD/Δf × 106 increased from 0.167 to 0.223, confirming that the CPAM layer adsorbed on the silica surface was thicker and more dissipative in 100 mM KCl solution. Meanwhile, the Δf of Chi-g-CPAM onto silica sensor changed from − 14.3 Hz to − 33.9 Hz. The conformation of Chi-g-CPAM layer changed slightly as the -ΔD/Δf × 106 increased from 0.174 to 0.186. From the AFM measurements in 1 mM and 100 mM KCl solution, the distance of adhesion forces between the silica probe and CPAM expanded from approximately 20 nm to around 50 nm, and the adhesion force changed from 1.9 nN± 0.1 nN to 21.3 nN± 0.1 nN. The interaction forces with a long range (∼100 nm) maintained at about 3 nN between the silica probe and Chi-g-CPAM. Such difference was mainly attributed to the steric hindrance effect originating from the shorter molecular chain of Chi-g-CPAM. In 100 mM KCl solution, the CPAM molecules with long chains had a more coiled conformation than Chi-g-CPAM, which resulted a train-like flat adsorption conformation and larger adhesion, and formed a loose and thick polymer layer of CPAM in high salinity. The insights into the flocculating performance in varying salinity solutions of CPAM and Chi-g-CPAM will contribute to the molecular design of chitosan-based flocculants for efficient wastewater treatment.