Forest productivity recovery or collapse? Model-data integration insights on drought-induced tipping points.

More frequent and severe droughts are driving increased forest mortality around the globe. We urgently need to describe and predict how drought affects forest carbon cycling and identify thresholds of environmental stress that trigger ecosystem collapse. Quantifying the effects of drought at an ecosystem level is complex because dynamic climate-plant relationships can cause rapid and/or prolonged shifts in carbon balance. We employ the CARbon DAta MOdel fraMework (CARDAMOM) to investigate legacy effects of drought on forest carbon pools and fluxes. Our Bayesian model-data fusion approach uses tower observed meteorological forcing and carbon fluxes to determine the response and sensitivity of aboveground and belowground ecological processes associated with the 2012-2015 California drought. Our study area is a mid-montane mixed conifer forest in the Southern Sierras. CARDAMOM constrained with gross primary productivity (GPP) estimates covering 2011-2017 show a ~75% reduction in GPP, compared to negligible GPP change when constrained with 2011 only. Precipitation across 2012-2015 was 45% (474 mm) lower than the historical average and drove a cascading depletion in soil moisture and carbon pools (foliar, labile, roots, and litter). Adding 157 mm during an especially stressful year (2014, annual rainfall = 293 mm) led to a smaller depletion of water and carbon pools, steering the ecosystem away from a state of GPP tipping-point collapse to recovery. We present novel process-driven insights that demonstrate the sensitivity of GPP collapse to ecosystem foliar carbon and soil moisture states-showing that the full extent of GPP response takes several years to arise. Thus, long-term changes in soil moisture and carbon pools can provide a mechanistic link between drought and forest mortality. Our study provides an example for how key precipitation threshold ranges can influence forest productivity, making them useful for monitoring and predicting forest mortality events.

Carbonized rice husk coated solar absorber for clean water generation from seawater with a solar still.

This study demonstrated the generation of clean water from seawater collected at the beach coast in Universiti Malaysia Sabah, Malaysia, with carbonized rice husk coated melamine sponge as solar absorber by a solar still. Melamine sponge was utilized as a seawater transportation medium since its porous structure is excellent in channelling the seawater. Whereas carbonized rice husk was used as the photothermal conversion material for its efficient heat absorption due to its black colour and porous structure. Implementing air gap between the seawater body and solar absorber, and restricted water pathway assisted in localizing heat on the top surface of the solar absorber. Clean water was generated under direct solar radiation during the day at an open space with average solar intensity around 1.1∼1.2 kW/m2 (slightly higher than 1 sun) for about 4 h. Efficiency of the solar absorber was calculated, while the quality of the generated clean water was observed in terms of salinity and pH value. Insulated solar still with carbon-coated sponge showed the highest efficiency at about 54.74%. Salinity of the collected clean water significantly reduced to consumable level which was approximately 55 ppm, and the pH value at about 6.73 where it was within the safe limit of the drinkable water pH.

Combining experimental and computational techniques to understand and improve dry powder inhalers.

INTRODUCTION: Dry Powder Inhalers (DPIs) continue to be developed to deliver an expanding range of drugs to treat an ever-increasing range of medical conditions; with each drug and device combination needing a specifically designed inhaler. Fast regulatory approval is essential to be first to market, ensuring commercial profitability. AREAS COVERED: In vitro deposition, particle image velocimetry, and computational modeling using the physiological geometry and representative anatomy can be combined to give complementary information to determine the suitability of a proposed inhaler design and to optimize its formulation performance. In combination, they allow the entire range of questions to be addressed cost-effectively and rapidly. EXPERT OPINION: Experimental techniques and computational methods are improving rapidly, but each needs a skilled user to maximize results obtained from these techniques. Multidisciplinary teams are therefore key to making optimal use of these methods and such qualified teams can provide enormous benefits to pharmaceutical companies to improve device efficacy and thus time to market. There is already a move to integrate the benefits of Industry 4.0 into inhaler design and usage, a trend that will accelerate.

Efficacy and safety of ivermectin for the treatment of COVID-19: a systematic review and meta-analysis.

BACKGROUND: Ivermectin became a popular choice for COVID-19 treatment among clinicians and the public following encouraging results from pre-print trials and in vitro studies. Early reviews recommended the use of ivermectin based largely on non-peer-reviewed evidence, which may not be robust. This systematic review and meta-analysis assessed the efficacy and safety of ivermectin for treating COVID-19 based on peer-reviewed randomized controlled trials (RCTs) and observational studies (OSs). METHODS: MEDLINE, EMBASE and PubMed were searched from 1 January 2020 to 1 September 2021 for relevant studies. Outcomes included time to viral clearance, duration of hospitalization, mortality, incidence of mechanical ventilation and incidence of adverse events. RoB2 and ROBINS-I were used to assess risk of bias. Random-effects meta-analyses were conducted. GRADE was used to evaluate quality of evidence. RESULTS: Three OSs and 14 RCTs were included in the review. Most RCTs were rated as having some concerns in regards to risk of bias, while OSs were mainly rated as having a moderate risk of bias. Based on meta-analysis of RCTs, the use of ivermectin was not associated with reduction in time to viral clearance, duration of hospitalization, incidence of mortality and incidence of mechanical ventilation. Ivermectin did not significantly increase incidence of adverse events. Meta-analysis of OSs agrees with findings from RCT studies. CONCLUSIONS: Based on very low to moderate quality of evidence, ivermectin was not efficacious at managing COVID-19. Its safety profile permits its use in trial settings to further clarify its role in COVID-19 treatment. PROTOCOL REGISTRATION: The review was prospectively registered in PROSPERO (CRD42021275302).

Barnacles as potential bioindicator of microplastic pollution in Hong Kong.

Microplastic (MP) pollution is an emerging problem in the marine environment and the assessment of the presence and abundance of microplastics in wild organisms is essential for risk assessment. The occurrence of microplastics in four species of barnacles at 30 sites in Hong Kong waters was investigated. The median number of microplastics ranged between 0 and 8.63 particles g-1 wet weight, or 0 and 1.9 particles individual-1, with fibers being the most abundant type of microplastics. The chemical composition of 152 pieces out of 606 potential microplastics was analyzed using micro-Fourier Transform Infrared Spectroscopy (µ-FTIR). Fifty-two of them were synthetic polymers, 95 natural cotton fibers and five unknowns. Eight types of polymer were identified with cellophane being the most abundant (58%). Correlation analysis was conducted between the abundance of MPs in sediments obtained in our previous study and that in individual barnacle species in this study, and a positive correlation was established for the barnacle Amphibalanus amphitrite, highlighting the potential of using this species as a bioindicator of microplastics.

Microplastics in invertebrates on soft shores in Hong Kong: Influence of habitat, taxa and feeding mode.

Microplastic (MP) pollution in the marine environment has gained much concern in recent years. This study investigated the occurrence of MPs in invertebrates collected on 18 mudflats and sandy beaches in Hong Kong and its relationships to biological taxon, feeding mode and habitat. In total 38 species of gastropods, bivalves and crabs were collected and the mean number of suspected microplastics ranged from 0 to 9.68 particles g-1 wet weight or 0 to 18.4 particles individual-1. Around 26% of the suspected microplastics were confirmed to be synthetic polymers, including CP (cellophane), PET (polyethylene terephthalate), and PA (polyamide). Microplastic fibres were the most abundant type of MPs, followed by pellets. Significantly higher abundance of suspected microplastics was found in gastropods. Since MP abundance might vary with taxon, it is recommended to include different taxonomic groups in any ecological assessment of the impact of MPs.

Appropriateness of deep vein thrombosis (DVT) prophylaxis use among medical inpatients: a DVT risk alert tool (DRAT) study.

INTRODUCTION: Increasing incidence of Venous Thromboembolism (VTE) has complicated treatment courses for hospitalised patients. Despite recommendation to support deep vein thrombosis (DVT) risk assessment and appropriate use of prophylaxis in medical inpatients, it is either neglected or prescribed unnecessarily by the clinicians. This study aimed to assess and compare the appropriateness of DVT prophylaxis prescribing between usual care versus a pharmacist-driven DVT Risk Alert Tool (DRAT) intervention among hospitalised medical patients. METHODS: A prospective pre- and post-intervention study was conducted among medical inpatients in a Malaysian secondary care hospital. DVT and bleeding risks were stratified using validated Padua Risk Assessment Model (RAM) and International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) Bleeding Risk Assessment Model. Pharmacist-driven DRAT was developed and implemented post-interventional phase. DVT prophylaxis use was determined and its appropriateness was compared between pre and post study using multivariate logistic regression with IBM SPSS software version 21.0. RESULTS: Overall, 286 patients (n=142 pre-intervention versus n=144 post-intervention) were conveniently recruited. The prevalence of DVT prophylaxis use was 10.8%. Appropriate thromboprophylaxis prescribing increased from 64.8% to 68.1% post-DRAT implementation. Of note, among high DVT risk patients, DRAT intervention was observed to be a significant predictor of appropriate thromboprophylaxis use (14.3% versus 31.3%; adjusted odds ratio=2.80; 95% CI 1.01 to 7.80; p<0.05). CONCLUSION: The appropriateness of DVT prophylaxis use was suboptimal but doubled after implementation of DRAT intervention. Thus, an integrated risk stratification checklist is an effective approach for the improvement of rational DVT prophylaxis use.

Migration of Aortic Occlusion Balloons in an in vitro model of the human circulation.

BACKGROUND: Aortic Occlusion Balloons (AOB) are used for hemorrhage control in hemodynamically unstable patients. Stability of an AOB is essential for reliable aortic occlusion. The primary aim of this study is to determine whether different types of AOB migrate after total, intermittent or partial occlusion in a porcine aorta positioned in an in vitro model. MATERIALS AND METHODS: A porcine thoracic aortic section was positioned in a model of the human circulation. Primary and secondary migration was tested in Cook Coda™ 2-9.0-35-120-32 and 2-10-35-140-46, Cook Medical, USA; Rescue balloon™ Tokai RB-167080-E, Tokai Medical Products, Japan; Reliant™ AB46, Medtronic, USA; Russian prototype AOB; ER-REBOA™, Prytime Medical Devices, USA; LeMaitre™ 28 and 45 Aortic Occlusion Catheter, LeMaitre Vascular, USA. These AOB were tested in hypotensive, normotensive and hypertensive scenarios. Migration in total occlusion, intermittent occlusion and partial occlusion was recorded for all AOB. RESULTS: Limited primary migration occurred in all AOB after total occlusion. The Cook Coda™ 2-9.0-35-120-32 balloon showed maximal migration in 1 test cycle. No migration occurred during intermittent occlusion. Kinking occurs in various degrees but does not seem to prevent a successful occlusion of the aorta. No migration occurred during partial occlusion except in the Russian prototype AOB. In a partial occlusion scenario, distal perfusion occurred only with 5 ml remaining in all balloon types. CONCLUSIONS: All AOB were successful in full aortic occlusion. Limited primary migration occurred in all AOB after total occlusion only the Cook Coda™ 2-9.0-35-120-32 balloon showed maximal migration once. No migration occurred during intermittent occlusion, during partial occlusion only the Russian prototype AOB migrated. Stiffness and size of the catheter are important factors in preventing migration and kinking.

Norepinephrine transporter expression is inversely associated with glycaemic indices: a pilot study in metabolically diverse persons with overweight and obesity.

OBJECTIVE: The objective of this study was to examine the cross-sectional relationship between the expression of norepinephrine transporter (NET), the protein responsible for neuronal uptake-1, and indices of glycaemia and hyperinsulinaemia, in overweight and obese individuals. METHODS: Thirteen non-medicated, non-smoking subjects, aged 58 ± 1 years (mean ± standard error of the mean), body mass index (BMI) 31.4 ± 1.0 kg m-2, with wide-ranging plasma glucose and haemoglobin A1c (HbA1c, range 5.1% to 6.5%) participated. They underwent forearm vein biopsy to access sympathetic nerves for the quantification of NET by Western blot, oral glucose tolerance test (OGTT), euglycaemic hyperinsulinaemic clamp, echocardiography and assessments of whole-body norepinephrine kinetics and muscle sympathetic nerve activity. RESULTS: Norepinephrine transporter expression was inversely associated with fasting plasma glucose (r = -0.62, P = 0.02), glucose area under the curve during OGTT (AUC0-120, r = -0.65, P = 0.02) and HbA1c (r = -0.67, P = 0.01), and positively associated with steady-state glucose utilization during euglycaemic clamp (r = 0.58, P = 0.04). Moreover, NET expression was inversely related to left ventricular posterior wall dimensions (r = -0.64, P = 0.02) and heart rate (r = -0.55, P = 0.05). Indices of hyperinsulinaemia were not associated with NET expression. In stepwise linear regression analysis adjusted for age, body mass index and blood pressure, HbA1c was an independent inverse predictor of NET expression, explaining 45% of its variance. CONCLUSIONS: Hyperglycaemia is associated with reduced peripheral NET expression. Further studies are required to identify the direction of causality.

Prediction of en-route complications during interfacility transport by outcome predictive scores in ED.

OBJECTIVE: The objective was to determine the accuracy of the outcome predictive scores (Modified Early Warning Score [MEWS]; Hypotension, Low Oxygen Saturation, Low Temperature, Abnormal ECG, Loss of Independence [HOTEL] score; and Simple Clinical Score [SCS]) in predicting en-route complications during interfacility transport (IFT) in emergency department. DESIGN: This was a retrospective cohort study. METHODS: All IFT cases by ambulances with either nurse-led or physician-led escort, occurring between 1 January 2011 and 31 December 2012, were included. Obstetric and pediatric cases (age < 18 years) were excluded. The condition of patients was quantified by using the predictive scores (MEWS, HOTEL, and SCS) at triage station and on ambulance departure. The accuracy of predictive scores was compared by the receiver operating characteristic (ROC) curves. RESULTS: A total of 659 cases were included. Seventeen cases had en-route complications (2.6%). The complication rate in physician-escorted transport (2.2%) was similar to that in nurse-escorted transport (2.6%). None of the 57 intubated cases had en-route complications. The area under the ROC curve for MEWS was 0.662 (triage) and 0.479 (departure). The accuracy of MEWS at triage was better than that at departure (P = .049). The area under the ROC curve for HOTEL was 0.613 (triage) and 0.597 (departure), and that for SCS was 0.6 (triage) and 0.568 (departure). In general, the predictive scores at triage were better than those on departure. CONCLUSION: None of the scores had good accuracy in prediction of en-route complications during IFT. MEWS at triage was among the best one already but was not ideal.

The SAD-MEN questionnaire: a new and reliable questionnaire for assessing sexual dysfunction in Asians with diabetes.

AIM: The aim of this study is to construct a new tool for the assessment of sexual dysfunction among men with diabetes that is valid and reliable across different ethnicities, languages and socio-economic backgrounds in South East Asia. METHODS: Focus group interviews were conducted to determine the construct of the questionnaire. Content and face validity were assessed by a panel of experts. A pilot study was conducted to validate the Sexual Dysfunction in Asian Men with Diabetes (SAD-MEN) questionnaire in English and Malay. The International Index of Erectile Function-5 (IIEF-5) was used for comparison. Construct validity was assessed using exploratory factor analysis, reliability was determined using Cronbach's α (> 0.700), and test-retest reliability using Spearman's rank correlation coefficient. RESULTS: The SAD-MEN questionnaire yielded moderate face and content validity, with high reliability as shown by Cronbach's α values of 0.949 for sexual performance and 0.775 for sexual desire for the English version. The Malay language questionnaire had a Cronbach's α value of 0.945 for sexual performance and 0.750 for sexual desire. Test-retest reliability using Spearman's test gave correlation coefficients of r = 0.853, P = 0.000 for the English language questionnaire and r = 0.908, P = 0.000 for the Malay language questionnaire. CONCLUSION: The SAD-MEN questionnaire is a valid and reliable tool by which to assess sexual dysfunction in English- and Malay-speaking Malaysian and South East Asian men with diabetes.

Active versus passive humidification for self-ventilating tracheostomy and laryngectomy patients: a systematic review of the literature.

OBJECTIVE: To determine whether active or passive humidification methods are more effective in preventing pulmonary complications in self-ventilating neck breather patients. DESIGN: Systematic Review adhering to PRISMA guidance (checklist sourced from www.equator-network.org/). SETTING: Review of current published relevant literature at a tertiary department of Otolaryngology and Head & Neck Surgery. PARTICIPANTS: We included all separate studies and comparison studies of active and passive humidification techniques in adult and paediatric neck breather patients. MAIN OUTCOME MEASURES: The primary outcome is the reduction in pulmonary complications. Secondary outcomes include patient compliance; carer and user satisfaction. RESULTS AND CONCLUSIONS: Seven studies were included in this review: two RCTs (133 patients), one randomised controlled cross-over trial (29 patients), three randomised prospective studies (171 patients), and one retrospective study (73 patients). Only one study was conducted on paediatric neck breathers. The overall quality of the studies was low. Five studies were at a high risk of bias. Of the remaining two studies, one study had a low risk of bias and the other had an unclear risk. Despite limited subject evidence, results show that passive methods of humidification (mainly HME) is the preferred choice of humidification in the spontaneously breathing neck breather patients group mainly due to the reduction in pulmonary complaints, and better patient compliance.

Double-burden of malnutrition among the indigenous peoples (Orang Asli) of Peninsular Malaysia.

BACKGROUND: Double-burden of malnutrition (DBM) is an emerging public health concern among the Orang Asli (indigenous peoples) of Peninsular Malaysia. This study aimed to identify the presence of DBM at the community and household levels in Orang Asli population and its associated demographic and socio-economic factors. METHODS: This cross-sectional study was conducted in 11 Orang Asli villages surrounding the Krau Wildlife Reserve, Peninsular of Malaysia from October 2011 to January 2012. Of 438 households, a total of 981 adults and 304 children who met the study criteria agreed to participate. About 160 households were further selected with pairs of children aged 3-59 months and non-pregnant mothers aged 15-55 years. Demographic and socio-economic data were obtained using interviewer-administered questionnaire while weight and height were measured using standard procedures. Double-burden of malnutrition was defined as overweight/obese mother-underweight child (OWOBM/UWC), overweight/obese mother-stunted child (OWOBM/STC) or overweight/obese mother-underweight or/and stunted child (OWOBM/UWSTC). Binary logistic regression identified the demographic and socio-economic factors associated with double-burden households. RESULTS: About 26 % of overweight and obese adults coexisting with high proportions of underweight (49%) and stunted (64%) children in these Orang Asli villages. There was a higher prevalence of households with OWOBM/UWSTC (20%) and OWOBM/STC (19.4%) than households with OWOBM/UWC (12.5%). Boys (P < 0.05), older age mothers (P < 0.05), mothers with higher education (P < 0.05) and households with income per capita less than USD 29.01 (RM 97.00) (P < 0.01) were associated with higher odds of OWOBM/STC. Jah Hut (P < 0.05) and higher number of children (P < 0.05) were significantly associated with lower odds of OWOBM/UWC. CONCLUSIONS: The occurrence of double-burden of malnutrition in Orang Asli population deserves attention. Poverty reduction, access to quality diet and improved health and nutrition literacy are among strategies that could address the coexistence of DBM in this population.

SR and LR Union Suture for the Treatment of Myopic Strabismus Fixus: Is Scleral Fixation Necessary?

PURPOSE: To evaluate and compare the effectiveness of scleral fixation SR and LR union suture and nonscleral fixation union suture for the treatment of myopic strabismus fixus. METHODS: Retrospective review of 32 eyes of 22 patients with myopic strabismus fixus who had undergone union suture of superior rectus (SR) and lateral rectus (LR) with or without scleral fixation, and follow-up longer than 6 months at Hong Kong Eye Hospital from 2006 to 2013. Surgical techniques and outcomes in terms of ocular alignment are analyzed. RESULTS: There is significant overall improvement both in postoperative angle of esodeviation (P < 0.01) and postoperative range of movement (P = 0.042). Comparing between the sclera fixation group (11 eyes) versus nonscleral fixation group (21 eyes), the postoperative horizontal deviation, the postoperative vertical deviation, successful outcome, and the change in horizontal deviation were not significantly different (P > 0.05). CONCLUSIONS: Union suture of SR and LR is an effective procedure in correcting myopic strabismus fixus. Fixation of the union suture to the sclera does not improve surgical outcome.

Maternal uptake of pertussis cocooning strategy and other pregnancy related recommended immunizations.

Maternal immunization is an important strategy to prevent severe morbidity and mortality in mothers and their offspring. This study aimed to identify whether new parents were following immunization recommendations prior to pregnancy, during pregnancy, and postnatally. A cross-sectional survey was conducted by a questionnaire administered antenatally to pregnant women attending a maternity hospital with a follow-up telephone interview at 8-10 weeks post-delivery. Factors associated with uptake of pertussis vaccination within the previous 5 y or postnatally and influenza vaccination during pregnancy were explored using log binomial regression models. A total of 297 pregnant women completed the questionnaire. For influenza vaccine, 20.3% were immunized during pregnancy and 3.0% postnatally. For pertussis vaccine, 13.1% were vaccinated within 5 y prior to pregnancy and 31 women received the vaccine postnatally, 16 (51.6%) received the vaccine >4 weeks after delivery. Receiving a recommendation from a healthcare provider (HCP) was an independent predictor for receipt of both pertussis (RR 2.07, p < 0.001) and influenza vaccine (RR 2.26, p = 0.001). Non-English speaking mothers were significantly less likely to have received pertussis vaccination prior to pregnancy or postnatally (RR 0.24, p = 0.011). Multiparous pregnant women were less likely to have received an influenza vaccine during their current pregnancy (p = 0.015). Uptake of pregnancy related immunization is low and likely due to poor knowledge of availability, language barriers and lack of recommendations from HCPs. Strategies to improve maternal vaccine uptake should include education about recommended vaccines for both HCPs and parents and written information in a variety of languages.

Elastin is a key regulator of outward remodeling in arteriovenous fistulas.

OBJECTIVES: Maturation failure is the major limitation of arteriovenous fistulas (AVFs) as hemodialysis access conduits. Indeed, 30-50% of AVFs fail to mature due to intimal hyperplasia and insufficient outward remodeling. Elastin has emerged as an important determinant of vascular remodeling. Here the role of elastin in AVF remodeling in elastin haplodeficient (eln(+/-)) mice undergoing AVF surgery has been studied. METHODS: Unilateral AVFs between the branch of the jugular vein and carotid artery in an end to side manner were created in wild-type (WT) C57BL/6 (n = 11) and in eln(+/-) mice (n = 9). Animals were killed at day 21 and the AVFs were analyzed histologically and at an mRNA level using real-time quantitative polymerase chain reaction. RESULTS: Before AVF surgery, a marked reduction in elastin density in the internal elastic lamina (IEL) of eln(+/-) mice was observed. AVF surgery resulted in fragmentation of the venous internal elastic lamina in both groups while the expression of the tropoelastin mRNA was 53% lower in the eln(+/-) mice than in WT mice (p < .001). At 21 days after AVF surgery, the circumference of the venous outflow tract of the AVF was 21% larger in the eln(+/-) mice than in the WT mice (p = .037), indicating enhanced outward remodeling in the eln(+/-) mice. No significant difference in intimal hyperplasia was observed. The venous lumen of the AVF in the eln(+/-) mice was 53% larger than in the WT mice, although this difference was not statistically significant (eln(+/-), 350,116 ± 45,073 µm(2); WT, 229,405 ± 40,453 µm(2); p = .064). CONCLUSIONS: In a murine model, elastin has an important role in vascular remodeling following AVF creation, in which a lower amount of elastin results in enhanced outward remodeling. Interventions targeting elastin degradation might be a viable option in order to improve AVF maturation.