Decolorization and control of bromate formation in membrane ozonation of humic-rich groundwater.

Membrane ozonation of bromide-containing, high-color natural organic matter (NOM) containing groundwater was performed using single-tube polydimethylsiloxane (PDMS) and multi-tube polytetrafluoroethylene (PTFE) membrane contactors, and compared to batch ozonation. For membrane ozonation, dissolved ozone concentration, water color (VIS436), ultraviolet light absorption (UV254) and bromate formation were correlated with ozone dose, ozone gas concentration, hydraulic retention time and Hatta number (Ha). NOM color removal of up to 45 % for the single-tube contactor and 17 % for the multi-tube contactor were achieved while containing bromate formation below 10 µg L-1. Higher color removal using higher ozone doses was associated with high bromate formation i.e. >>10 µg L-1. In membrane ozonation, low ozone gas concentrations, long hydraulic retention times and high Ha resulted in low dissolved ozone concentrations due to quenching of ozone by NOM. At specific ozone doses of < 0.5 mg O3/mg DOC and Ha > 1, single-tube ozonation resulted in comparable results to batch ozonation while bromate formation was higher in the single-tube contactor at specific ozone doses > 0.5 mg O3/mg DOC and Ha < 1. At comparable ozone doses and Ha, bromate formation in the multi-tube contactor was always higher compared to single-tube and batch ozonation. This could be associated with the uneven ozone distribution within the multi-tube contactor. Results show that ozone dose is the major driver for selectivity between bromate formation and NOM color removal in both membrane and batch ozonation. Bromate formation in membrane ozonation may be controlled by adjusting gas concentration, Ha and hydraulic retention time. Membrane module design and process parameters of membrane ozonation reactors significantly affect treatment performance and should be optimized for selective target compound removal over by-product formation.

Enhanced nanoparticle rejection in aligned boron nitride nanotube membranes.

The rejection of particles with different charges and sizes, ranging from a few Ångstroms to tens of nanometers, is key to a wide range of industrial applications, from wastewater treatment to product purification in biotech processes. Carbon nanotubes (CNTs) have long held the promise to revolutionize filtration, with orders of magnitude higher fluxes compared to commercial membranes. CNTs, however, can only reject particles and ions wider than their internal diameter. In this work, the fabrication of aligned boron nitride nanotube (BNNT) membranes capable of rejecting nanoparticles smaller than their internal diameter is reported for the first time. This is due to a mechanism of charge-based rejection in addition to the size-based one, enabled by the BNNTs surface structure and chemistry and elucidated here using high fidelity molecular dynamics and Brownian dynamics simulations. This results in ∼40% higher rejection of the same particles by BNNT membranes than CNT ones with comparable nanotube diameter. Furthermore, since permeance is proportional to the square of the nanotubes' diameter, using BNNT membranes with ∼30% larger nanotube diameter than a CNT membrane with comparable rejection would result in up to 70% higher permeance. These results open the way to the design of more effective nanotube membranes, capable of high particle rejection and, at the same time, high water permeance.

Comparison of Macintosh Laryngoscopy in Bed-up-Head-Elevated Position With GlideScope Laryngoscopy: A Randomized, Controlled, Noninferiority Trial.

BACKGROUND: Approximately half of all difficult tracheal intubations (DTIs) are unanticipated; hence, proper positioning during intubation is critical to increase the likelihood of success. The bed-up-head-elevated (BUHE) intubation position has been shown to improve laryngeal view, reduce airway complications, and prolong safe apneic time during intubation. In this study, we sought to determine whether the BUHE intubation position is noninferior to Glidescope (GLSC)-assisted intubation with regard to laryngeal exposure. METHODS: A total of 138 American Society of Anesthesiologists (ASA) I to III patients were randomly assigned into 2 groups and underwent baseline laryngoscopy in the sniffing position. Group BUHE patients (n = 69) were then intubated in the BUHE position, while group GLSC patients (n = 69) were intubated using GLSC laryngoscopy. Laryngeal exposure was measured using Percentage of Glottic Opening (POGO) score and Cormack-Lehane (CL) grading, and noninferiority will be declared if the difference in mean POGO scores between both groups do not exceed -15% at the lower limit of a 98% confidence interval (CI). Secondary outcomes measured included time required for intubation (TRI), number of intubation attempts, use of airway adjuncts, effort during laryngoscopy, and complications during intubation. RESULTS: Mean POGO score in group BUHE was 80.14% ± 22.03%, while in group GLSC it was 86.45% ± 18.83%, with a mean difference of -6.3% (98% CI, -13.2% to 0.6%). In both groups, there was a significant improvement in mean POGO scores when compared to baseline laryngoscopy in the sniffing position (group BUHE, 25.8% ± 4.7%; group GLSC, 30.7% ± 6.8%) (P < .0001). The mean TRI was 36.23 ± 14.41 seconds in group BUHE, while group GLSC had a mean TRI of 44.33 ± 11.53 seconds (P < .0001). In patients with baseline CL 3 grading, there was no significant difference between mean POGO scores in both groups (group BUHE, 49.2% ± 19.6% versus group GLSC, 70.5% ± 29.7%; P = .054). CONCLUSIONS: In the general population, BUHE intubation position provides a noninferior laryngeal view to GLSC intubation. The laryngeal views obtained in both approaches were superior to the laryngeal view obtained in the sniffing position. In view of the many advantages of the BUHE position for intubation, the lack of proven adverse effects, the simplicity, and the cost-effectiveness, we propose that clinicians should consider the BUHE position as the standard intubation position for the general population.

3D Printed Fouling-Resistant Composite Membranes.

Fouling remains a long-standing unsolved problem that hinders the widespread use of membrane applications in industry. This article reports the use of numerical simulations coupled with extensive material synthesis and characterization to fabricate fouling-resistant 3D printed composite membranes. The membranes consist of a thin polyethersulfone selective layer deposited onto a 3D printed flat and double sinusoidal (wavy) support. Fouling and cleaning of the composite membranes were tested by using bovine serum albumin solution in a cross-flow ultrafiltration setup. The transmembrane pressure was regulated at 1 bar and the cross-flow Reynolds number (Re) varied between 400 and 1000. In comparison to the flat membrane, the wavy membrane showed superior performance in terms of pure water permeance (PWP) (10% higher) and permeance recovery ratio (87% vs 53%) after the first filtration cycle at Re = 1000. Prolong testing showed that the wavy membrane could retain approximately 87% of its initial PWP after 10 complete filtration cycles. This impressive fouling-resistant behavior is attributed to the localized fluid turbulence induced by the 3D printed wavy structure. These results show that not only the lifetime of membrane operations could be favorably extended but also the operational costs and environmental damage of membrane-based processes could also be significantly reduced.

Surface-Controlled Water Flow in Nanotube Membranes.

The independent effect of nanotube surface chemistry and structure on the flow of water under nanoscale confinement is demonstrated in this paper for the first time via the synthesis of novel carbon nitride nanotube (CNNT) membranes. Using a combination of experiments and high-fidelity molecular dynamics (MD) simulations, it is shown here that the hydrophilization of the sp2 carbon structure, induced by the presence of the C-N bonds, decreases the pure water permeance in CNNTs when compared with pristine and turbostratic carbon nanotubes (CNTs). The MD simulations are based on a model true to the chemical structure of the synthesized nanotubes, built from spectroscopy measurements and calibrated potentials using droplet experiments. The effect on permeance is explained in terms of solid-liquid interactions at the nanotube wall with increased water viscosity and decreased surface diffusion near the CNNT wall, when compared to CNTs. A model directly linking the solid-liquid interactions to the water permeance is presented, showing good agreement with both experiments and MD simulations. This work opens the way to tailoring surface chemistry and structure inside nanotube membranes for a wide range of transport and separation processes.

On-line biofilm strength detection in cross-flow membrane filtration systems.

A fluid dynamic gauging (FDG) technique was used for on-line and in situ measurements of Pseudomonas aeruginosa PAO1 biofilm thickness and strength on flat sheet polyethersulphone membranes. The measurements are the first to be successfully conducted in a membrane cross-flow filtration system under constant permeation. In addition, FDG was used to demonstrate the removal behaviour of biofilms through local biofilm strength and removal energy estimation, which other conventional measurements such as flux and TMP cannot provide. The findings suggest that FDG can provide valuable additional information related to biofilm properties that have not been measured by other monitoring methods.

Pneumocephalus Following Combined Spinal Epidural Anaesthesia for Total Knee Arthroplasty: A Case Report.

The authors describe a case of pneumocephalus following epidural anaesthesia for total knee arthroplasty. Multiple attempts in locating the epidural space for the anaesthesia and the use of loss of resistance to air (LORA) technique were identified as the source of air entry. Supportive management was given including high flow oxygenation therapy and spontaneous reabsorption of air was noted five days after surgery. The presence of pneumocephalus should be kept in mind if patient develops neurological complications postoperatively following epidural anaesthesia.

The ABC's of Suicide Risk Assessment: Applying a Tripartite Approach to Individual Evaluations.

There is considerable need for accurate suicide risk assessment for clinical, screening, and research purposes. This study applied the tripartite affect-behavior-cognition theory, the suicidal barometer model, classical test theory, and item response theory (IRT), to develop a brief self-report measure of suicide risk that is theoretically-grounded, reliable and valid. An initial survey (n = 359) employed an iterative process to an item pool, resulting in the six-item Suicidal Affect-Behavior-Cognition Scale (SABCS). Three additional studies tested the SABCS and a highly endorsed comparison measure. Studies included two online surveys (Ns = 1007, and 713), and one prospective clinical survey (n = 72; Time 2, n = 54). Factor analyses demonstrated SABCS construct validity through unidimensionality. Internal reliability was high (α = .86-.93, split-half = .90-.94)). The scale was predictive of future suicidal behaviors and suicidality (r = .68, .73, respectively), showed convergent validity, and the SABCS-4 demonstrated clinically relevant sensitivity to change. IRT analyses revealed the SABCS captured more information than the comparison measure, and better defined participants at low, moderate, and high risk. The SABCS is the first suicide risk measure to demonstrate no differential item functioning by sex, age, or ethnicity. In all comparisons, the SABCS showed incremental improvements over a highly endorsed scale through stronger predictive ability, reliability, and other properties. The SABCS is in the public domain, with this publication, and is suitable for clinical evaluations, public screening, and research.

Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists.

To elucidate the genetic bases of mycorrhizal lifestyle evolution, we sequenced new fungal genomes, including 13 ectomycorrhizal (ECM), orchid (ORM) and ericoid (ERM) species, and five saprotrophs, which we analyzed along with other fungal genomes. Ectomycorrhizal fungi have a reduced complement of genes encoding plant cell wall-degrading enzymes (PCWDEs), as compared to their ancestral wood decayers. Nevertheless, they have retained a unique array of PCWDEs, thus suggesting that they possess diverse abilities to decompose lignocellulose. Similar functional categories of nonorthologous genes are induced in symbiosis. Of induced genes, 7-38% are orphan genes, including genes that encode secreted effector-like proteins. Convergent evolution of the mycorrhizal habit in fungi occurred via the repeated evolution of a 'symbiosis toolkit', with reduced numbers of PCWDEs and lineage-specific suites of mycorrhiza-induced genes.

Rare embryonal rhabdomyosarcoma of external acoustic canal: a case report and literature review.

Embryonal rhabdomyosarcoma of external ear canal is very rare, even in the pediatric population. We report an embryonal rhabdomyosarcoma of external acoustic canal, occurring in a 12-year-old Chinese girl who presented with left ear canal mass. Wide local excision of the mass was done under local anesthesia. Histopathological examination revealed the diagnosis. She then underwent 20 cycles of radiotherapy. CECT scan post treatment showed clearance of tumor cell. Now, patient is disease free for 5 years. We believe that early diagnosis followed by complete resection of the tumor with clear margin and radiotherapy improves the prognosis of the disease.

Free-energy-based lattice Boltzmann model for the simulation of multiphase flows with density contrast.

A free-energy-based phase-field lattice Boltzmann method is proposed in this work to simulate multiphase flows with density contrast. The present method is to improve the Zheng-Shu-Chew (ZSC) model [Zheng, Shu, and Chew, J. Comput. Phys. 218, 353 (2006)] for correct consideration of density contrast in the momentum equation. The original ZSC model uses the particle distribution function in the lattice Boltzmann equation (LBE) for the mean density and momentum, which cannot properly consider the effect of local density variation in the momentum equation. To correctly consider it, the particle distribution function in the LBE must be for the local density and momentum. However, when the LBE of such distribution function is solved, it will encounter a severe numerical instability. To overcome this difficulty, a transformation, which is similar to the one used in the Lee-Lin (LL) model [Lee and Lin, J. Comput. Phys. 206, 16 (2005)] is introduced in this work to change the particle distribution function for the local density and momentum into that for the mean density and momentum. As a result, the present model still uses the particle distribution function for the mean density and momentum, and in the meantime, considers the effect of local density variation in the LBE as a forcing term. Numerical examples demonstrate that both the present model and the LL model can correctly simulate multiphase flows with density contrast, and the present model has an obvious improvement over the ZSC model in terms of solution accuracy. In terms of computational time, the present model is less efficient than the ZSC model, but is much more efficient than the LL model.

Effects of pharmaceutical care on adherence and persistence to bisphosphonates in postmenopausal osteoporotic women.

WHAT IS KNOWN AND OBJECTIVE: Studies have shown that comprehensive interventions by pharmacists can improve adherence and persistence to osteoporosis therapy, but the association between adherence and bone turnover markers (BTMs) has never been studied. Therefore, the aim of this study was to evaluate the effects of pharmaceutical care on medication adherence (and its effects on BTMs), as well as persistence of postmenopausal osteoporotic women to prescribed bisphosphonates. METHODS: A randomized controlled trial was conducted from 2005 to 2009 in the University Malaya Medical Centre, Malaysia. INCLUSION CRITERIA: postmenopausal osteoporotic women diagnosed with osteoporosis with a T-score ≤ -2·5 or who had a low-trauma fracture and prescribed weekly alendronate/risedronate. Intervention participants received counselling on osteoporosis, risk factors, lifestyle modifications, goals of therapy, side effects and the importance of adherence. Adherence was assessed at months 3, 6 and 12, and persistence at month 12. Feedback on BTMs was provided at months 4 and 7. The control group received no counselling. Two BTMs were used: serum C-terminal cross-linking telopeptide of type I collagen (CTX-I) and serum osteocalcin (OC). MAIN OUTCOMES MEASURED: medication adherence, BTMs and persistence. RESULTS AND DISCUSSION: Intervention participants who received pharmaceutical care reported significantly higher medication adherence at 6 (P = 0·015) and 12 months (P = 0·047) compared with the control group; but this effect was not shown by the BTMs. This is probably due to the long effect of bisphosphonates in bone. A significant difference was found between serum CTX-I and OC in identifying non-responders to anti-resorptive therapy (P < 0·001), indicating the usefulness of BTMs as an objective marker. However, pharmaceutical care did not affect persistence to osteoporosis therapy within a 1-year period [log rank (Mantel-Cox) χ² = 0·496, P = 0·481]. The proportion of participants who were persistent with bisphosphonate therapy after 12 months was 89·8% and 87·0% in the control and intervention group respectively. WHAT IS NEW AND CONCLUSION: The provision of pharmaceutical care improved medication adherence but not persistence. BTMs were not appropriate objective measures for assessing adherence to weekly bisphosphonates but were useful for identifying non-responders to treatment within 3-6 months, much earlier than using bone mineral density. The study indicates that pharmacists have a role in improving medication adherence, but its long-term effect on persistence warrants further studies with longer duration.

Subcutaneous metastasis of olfactory neuroblastoma - an uncommon presentation.

Olfactory neuroblastoma is a rare, slow growing, malignant tumour of neuroectodermal origin that begins in neuroepithelial cells of the olfactory membrane. A metastatic rate of 20% to 60% is reported with the most common site being the cervical lymph node. Other sites include the parotid glands, skin, lungs, bone, liver, orbit, spinal cord and spinal canal. We describe a case of olfactory neuroblastoma presented to us with scalp metastasis.

Frontal mucocoele secondary to nasal polyposis: an unusual complication.

The incidence of mucocoeles associated with a non-surgically treated nasal polyposis is rare. We report a rare case of nasal polyposis with asymptomatic frontal mucocoeles in a 28-year-old Malay man who presented with bilateral nasal obstruction with anosmia. Physical examination revealed bilateral grade III nasal polyps causing obstruction. Computed tomography revealed paranasal polyposis with a large polyp extending and expanding the posterior table of the frontal sinus causing erosion and thinning of its wall. Marsupialisation of the mucocoele and nasal polypectomy were done. Endoscopic sinus surgery and marsupialisation should be the treatment of choice for asymptomatic frontal mucocoele.

Determination of trimester specific reference intervals for thyroid hormones during pregnancy in Malaysian women.

OBJECTIVE: To establish trimester specific reference intervals for thyroid hormones during pregnancy in Malaysian women. STUDY DESIGN: Cross-sectional observational study performed in the Obstetric Clinic, University Malaya Medical Centre. A single blood sample from 626 women at various trimesters of pregnancy was analyzed for thyroid function. TSH, FT4, TT4, FT3 and TT3 values at each trimester of pregnancy were calculated. RESULTS: From the TSH, FT4, TT4, FT3 and TT3 results, reference values based on mean +/- 2SD was calculated for the hormones at each trimester of pregnancy. CONCLUSION: We calculated clinically relevant trimester-specific reference values for thyroid function tests through pregnancy to facilitate improved management of thyroid disease in pregnancy in our local population.

Interference of hemoglobinA1c (HbA1c) detection using ion-exchange high performance liquid chromatography (HPLC) method by clinically silent hemoglobin variant in University Malaya Medical Centre (UMMC)--a case report.

BACKGROUND: Glycated hemoglobin, measured as HbA1c is used as an index of mean glycemia in diabetic patients over the preceding 2-3 months. Various assay methods are used to measure HbA1c and many factors may interfere with its measurement according to assay method used, causing falsely high or low results. OBJECTIVE: To report a case of diabetic patient with clinically silent hemoglobin variant, causing undetectable HbA1c concentration using ion-exchange high performance liquid chromatography (HPLC) method. CASE SUMMARY: Our patient is a 65-year-old female with type 2 diabetes mellitus on diet control, hypertension and hypercholesterolemia. Her fasting blood glucose concentrations ranged from 6.2 to 7.8 mmol/L. Her HbA1c concentrations measured with immunoturbidimetry method (Cobas Integra, Roche Diagnostics) ranged from 6.11 to 7.23%, but were undetectable when measured with ion-exchange HPLC [Arkray HA8160, Diabetes Mode (also known as Menarini HA8160)]. Hemoglobin analysis identified the presence of a hemoglobin variant--Hemoglobin D Punjab. CONCLUSIONS: Clinical laboratories should be aware of limitations of the HbA1c assay method used, such as potential interference with hemoglobin variant as depicted by our case. Alternative methods for monitoring glycemic control in these patients should be considered.

Parotid abscess: an unusual cause of facial nerve palsy.

Facial nerve palsy with a parotid mass is usually associated with malignant neoplasm of parotid gland. Its occurrence as a complication of parotid abscess is extremely rare. A literature review revealed only 16 cases of facial nerve palsy associated with suppurative parotitis or parotid abscess were reported. We present a case of deep parotid abscess which is complicated by facial nerve dysfunction. Underlying neoplasia was excluded.

Leiomyosarcoma of the maxillary sinus.

Leiomyosarcoma is a malignant smooth-muscle tumour that has a predilection for the gastrointestinal and female genital tract. It is locally fast-spreading and highly aggressive, and the prognosis is poor. We report a rare case of leiomyosarcoma of the maxilla in a patient who sought treatment for maxillary swelling, nasal obstruction with no epistaxis, orbital involvement or cervical lymph node metastasis. The patient underwent subtotal maxillectomy followed by radiotherapy. At present, he is symptom free with no recurrence and under regular follow up.

A complete transection of larynx.

Acute laryngeal injury is a rare, potentially lethal injury. It often poses difficulty in airway management. Commonly described are external laryngeal or blunt injuries. We report a case of penetrating neck injury resulting in complete transection of cricoid cartilage. A lady presented with a large, deep slash wound in her neck from a knife injury. There was complete laryngotracheal separation. The airway was secured before she was taken to the operating theatre. A tracheostomy was performed. Exploration revealed the cricoid ring was cut horizontally into two. Anastomosis of the cartilaginous framework was undertaken. Fibreoptic laryngoscopy showed bilateral vocal cords paralysis. After two months the patient recovered without airway compromise, she regains her voice. Repeat laryngoscopy showed good mobility of the vocal cords. In conclusion surgical reconstruction should be meticulously done to ensure good respiratory and phonatory abilities.

Numerical investigation of transporting droplets by spatiotemporally controlling substrate wettability.

Droplet behaviors on substrates with wettability controlled both in space and in time are numerically investigated by using the lattice Boltzmann method. Several typical droplet responses are found under different designs of substrate wettability control. Special attention is drawn to the conditions under which rapid transport of droplets can be achieved. It is found that on alternating non-wetting-wetting units with proper non-wetting confining stripes, this objective can be realized when the frequency of wettability switch approximately matches that of the droplet to move across one unit. The variation of the "optimal" frequency with the size of the confining stripe is sought within certain ranges. The various types of droplet movement are analyzed by looking at the three-phase lines on the substrate, as well as the droplet shapes under different conditions. The results may provide useful implications for droplet manipulation in microfluidic devices.