Grit particle characterization: influence of sample pretreatment and sieving method.

Grit causes problems in water resource recovery facilities (WRRFs): clogging pipes, damaging pumps, and reducing the active volume of aeration tanks and anaerobic digesters by grit accumulation. Grit chambers are built to remove these particles. However, no standardized methodology exists to characterize grit particles for grit chamber design and operation despite the large observed variability in grit composition. Therefore, this paper proposes a combination and adaptation of existing methods to sample and characterize grit particles in view of proper grit chamber design and its modelling to ultimately optimize the efficiency of this important WRRF unit process. Characteristics evaluated included particle size distribution from sieving after different sample pretreatments, organic/inorganic fractions, and density.

Image-guided transnasal endoscopic fine needle aspiration or biopsy of parapharyngeal space tumours.

BACKGROUND: Parapharyngeal space biopsy is an important investigation in the management of parapharyngeal space tumours. These tumours are relatively rare and the surgeon is often faced with a wide range of differential diagnoses. There are several ways to access the parapharyngeal space, with varying degrees of associated morbidity. METHODS: This paper describes a seldom used, but a simple and safe, image-guided endoscopic approach to parapharyngeal space biopsy that enables tissue to be obtained transnasally. The procedure is conducted under general anaesthesia using computed tomography image guidance via the LandmarX system, with transnasal access to the parapharyngeal space achieved using a sampling needle. RESULTS: This procedure is relatively simple, safe and reproducible. It is a less invasive approach to parapharyngeal space biopsy, and one which has been successfully used by the senior author for years without any significant morbidity. CONCLUSION: Transnasal image-guided endoscopic aspiration or biopsy of the parapharyngeal space is a novel technique that has not been previously described.

Carboxylic acid derivatives via catalytic carboxylation of unsaturated hydrocarbons: whether the nature of a reductant may determine the mechanism of CO2 incorporation?

Application of CO2 as a renewable feedstock and C1 building block for production of commodity and fine chemicals is a highly challenging but obvious industry-relevant task. Of particular interest is the catalytic coupling of CO2 with inexpensive unsaturated hydrocarbons (olefins, dienes, styrenes, alkynes), providing direct access to carboxylic acids and their derivatives. Although not brand new for the scientific community, it is still a complete challenge, as no truly effective catalytic system has been reported to date. In this Perspective, we discuss the available experimental, theoretical and mechanistic data for such homogeneously catalyzed carboxylation processes. A special focus is placed on the understanding of the key elementary steps and of some thermodynamic and kinetic constraints.

Ethylene oligomerization promoted by chromium complexes bearing pyrrolide-imine-amine/ether tridentate ligands.

Chromium(iii) complexes [CrCl2(L)(THF)] based on monoanionic tridentate ligands [, L = {2-(C4H3N-2'-CH[double bond, length as m-dash]N)C2H4NHPh}; , L = {5-tert-butyl-2-(C4H2N-2'-CH[double bond, length as m-dash]N)C2H3NHPh}; , L = {2-(C4H3N-2'-CH[double bond, length as m-dash]N)C2H4OPh}] have been prepared. Complexes and were converted into the monomeric acetonitrile adducts [CrCl2(L)(NCMe)] [, L = {2-(C4H3N-2'-CH[double bond, length as m-dash]N)C2H4NHPh}; , L = {5-tert-butyl-2-(C4H2N-2'-CH[double bond, length as m-dash]N)C2H3NHPh}] by reaction with acetonitrile at room temperature. All Cr complexes were characterized by IR spectroscopy, elemental analysis, magnetochemistry for , and by X-ray crystallography for and . Upon activation with methylaluminoxane (MAO), chromium precatalysts and showed good activity in ethylene oligomerization (TOF = 47.0-57.0 × 10(3) (mol ethylene)(mol Cr)(-1) h(-1) at 80 °C), producing mostly oligomers (93.0-95.6 wt% of total products). On the other hand, under identical oligomerization conditions, /MAO behaved as a polymerization catalyst generating predominantly polyethylene (73.0 wt%). However, the catalytic behavior of the precatalyst can be adjusted by varying the MAO-to-Cr ratio. Thus, the use of 500 equiv. causes a dramatic shift from polymerization to ethylene oligomerization, eventually producing mainly lighter α-olefin fractions [α-C4 (68.7 wt%) and α-C6 (19.2 wt%)]. A further increase in the amount of MAO (1000 equiv.) leads to a more balanced distribution of oligomers, with a drastic decrease in the α-C4 and increase in the α-C8 fractions.

Dinuclear vs. mononuclear complexes: accelerated, metal-dependent ring-opening polymerization of lactide.

Dinuclear complexes of aluminum and indium with a bis(phenoxy-imine) platform have been synthesized and used in the polymerization of lactide. Kinetic studies demonstrate that the dialuminum precursor provides a more favorable reaction pathway in terms of activation free energy than that of directly related monoaluminum systems. No similar trend is observed with the corresponding diindium-monoindium systems, which is attributed to a dissimilar ROP mechanism.

Musical hallucination following whiplash injury: case report and literature review.

INTRODUCTION: A musical hallucination is defined as a form of auditory hallucination characterised by the perception of music in the absence of external acoustic stimuli. It is infrequently cited in the literature, although population studies suggest a greater prevalence. The aetiology of this unusual disorder remains unclear. CASE REPORT: A 70-year-old man with acquired hearing loss suffered a whiplash injury in a low-speed road traffic accident, and subsequently presented with bilateral 'tinnitus.' On closer questioning, he described hearing orchestral music. There was no evidence of psychosis, delirium or intoxication, and the patient was managed expectantly. CONCLUSION: This patient represents the first published case of musical hallucination precipitated by whiplash injury. We explore the possible pathophysiological underpinnings of musical hallucination and highlight the need for a greater awareness of this disorder. A management strategy is suggested.

[Aortic thrombi associated with thoracic gunshot wound]. / Thrombus aortique compliquant un traumatisme thoracique balistique.

We report the case of a stroke due to a ballistic thoracic traumatism. The vascular injury, provoked by the passage of the bullet, associated to a procoagulating state led to the formation of a thrombus in the ascending aorta. The migration of this thrombus caused a stroke, finally reversible upon medical treatment only.

Safety of sublingual grass pollen immunotherapy after anaphylaxis.

AIM: To demonstrate that sublingual immunotherapy is a safe treatment option in patients who have previously suffered anaphylaxis when undergoing subcutaneous grass pollen immunotherapy. CASE REPORT: We report two patients who developed a systemic anaphylactic reaction following subcutaneous grass pollen immunotherapy, resulting in discontinuation of treatment. Following treatment of the acute anaphylactic episode, both patients were subsequently safely commenced on sublingual grass pollen immunotherapy. CONCLUSION: Injection immunotherapy has a relatively low risk of severe adverse events, although anaphylaxis is a potentially fatal complication and usually results in termination of the immunotherapy programme. Sublingual immunotherapy has a safer side effect profile than subcutaneous immunotherapy, with no reported cases of anaphylaxis.

A preliminary randomised controlled trial evaluating the efficacy of saline douching following endoscopic sinus surgery.

OBJECTIVE: To assess whether saline reduces postoperative signs following endoscopic sinus surgery (ESS). DESIGN: Within subject, single blinded randomised controlled trial. SETTING: Single secondary referral centre. PARTICIPANTS: Adults undergoing bilateral ESS for chronic rhinosinusitis or nasal polyposis. INTERVENTION: Saline douching of one side of the nasal cavity, three times per day for 6 weeks. MAIN OUTCOME MEASURES: Presence of adhesions, polyps, crusting, discharge or oedema under endoscopic examination at 3 weeks and 3 months postoperative. RESULTS: Twenty-three patients were recruited. Attendance was 22 patients at 3 weeks and 17 patients at 3 months. At 3 weeks saline douching significantly improved the presence of discharge (P = 0.046) and non-significantly improved the presence of oedema (P = 0.059) with minimal difference with regard to polyps (P = 0.32) and no difference with adhesions or crusting. At 3 months there was minimal difference with regard to crusting (P = 0.18) and oedema (P = 0.32) and no difference with adhesions, discharge and polyps. CONCLUSIONS: Saline douching reduces nasal discharge and may improve oedema during the healing phase following ESS which may represent a possible anti-inflammatory role. No long-term effect was found.

Nasal septal perforation and antiphospholipid syndrome (Hughes syndrome).

We present the case of a 19-year-old woman who developed a nasal septal perforation and atrophic rhinitis following septal surgery. During the subsequent five years, she also experienced intermittent episodes of swelling and ischaemia of the left foot, as well as livedo reticularis. Ultimately, haematological investigations revealed the presence of lupus anticoagulant and elevated antiphospholipid immunoglobulin M levels. A diagnosis of antiphospholipid syndrome (Hughes syndrome) was made.A search of the literature revealed that nasal septal perforation has been described in up to 0.8 per cent of patients with antiphospholipid syndrome. However, it is undescribed in the otorhinolaryngological literature. The impact of this syndrome on otorhinolaryngology practice is examined.

Endoscopic dacrocystorhinostomy in lacrimal canalicular trauma.

A case is presented where the common insertion of the upper and lower canaliculus of the lacrimal sac was repaired using endoscopic dacrocystorhinostomy (DCR) techniques, with silicone stenting and securing of stents intranasally.

[Severe imported malaria in adults]. / Paludisme grave d'importation de l'adulte.

Severe malaria is characterized by the presence of asexual forms of Plasmodium falciparum in the blood and the presence of one or more OMS 2000 criterion. Imported malaria is defined as malarial infection acquired in an endemic country (often in sub-Saharan Africa) and treated in France. The largest patient group includes African patients, long-term residents in France, coming back from a vacation in their native country. In non-immunized adults, severe malaria causes multiple organe failure such as severe Gram-negative sepsis, with variable degrees of altered mental status. Severe sepsis is treated in an intensive care unit (mechanically assisted ventilation, kidney dialysis, vasoconstrictors...). Intravenous quinine is the reference treatment, but artemisinin derivatives (arthemeter and artesunate) are the most rapidly acting antimalarial drugs.

[Ketamine: drug facts, uses in anesthesia, and new applications for analgesia]. / La kétamine rappels pharmacologiques, utilisations en anesthésie et nouveautés pour l'analgésie.

Ketamine is an anesthetic drug of choice in tropical zones. In addition to excellent pharmocologic properties and low cost, it offers the possibility of using a variety of administration routes and of performing invasive procedures with spontaneous ventilation. Adverse psychodysleptic effects can be prevented by association with midazolam or propofol. Hypersalivation can be prevented with atropine. Recent experience has shown that thanks to its antihyperalgesic effects ketamine can be used for postoperative analgesia at doses ten times lower than for anesthesia.

How we do it: adjunctive intravenous midazolam: diagnosis and treatment of therapy-resistant muscle tension dysphonia.

Dysphonic patients with muscle tension are common at voice clinics. The majority respond to intensive vocal therapy. A small number of cases remain resistant to intensive vocal therapy. We have used intravenous midazolam to enhance therapy-resistant dysphonic patients' self-monitoring, their self-awareness and to change fixed patterns. Six of seven patients were discharged with restoration of normal voice 1 month after treatment.

Reconstituting middle turbinate anatomy after pituitary surgery.

Pituitary surgery is now increasingly performed as a joint procedure combining the expertise of a neurosurgeon and an otorhinolaryngologist. As endoscopic sinus surgery is currently one of the commonest surgical procedures performed by ear, nose and throat surgeons, familiarity of sphenoid sinus anatomy over several years of training becomes second nature to those with this interest. The endoscopic approach to the pituitary fossa via the sphenoid sinus allows a minimally invasive approach, thus reducing postsurgical morbidity and duration of hospital stay. The surgical approach involves lateralization of the middle turbinate followed by burring away of the face of the sphenoid air cell. Those without experience of sinus surgery may neglect to reconstitute the position of the middle turbinate at completion of surgery. Further mucosal contraction, scarring and synechiae formation will cause spontaneous lateralization of the middle turbinate during the healing period. This may predispose the patient to chronic sinusitis as a consequence of occlusion at the critical osteomeatal complex. The most satisfactory postoperative results are achieved by maintaining patency of the middle meatus. This will allow sinus aeration and drainage, and the delivery of topical medication should this be required. This paper describes a conchopexy suture placed at completion of pituitary fossa surgery. A carefully placed suture will maintain a widely patent middle meatus during the phase of postoperative healing, thus reducing the risk of chronic sinusitis.

[Assessment of transfusion requirements: a way to in improve perioperative management of blood products?]. / Evaluation du besoin transfusionnel un moyen d'améliorer la gestion des produits sanguins durant la période périopératoire?

Autogenic blood transfusion is indispensable in emergency surgery situations involving severe blood loss. It may also be required in some non-emergency surgical and obstetrical situations. The use of blood-sparing techniques as an alternative to autogenic blood transfusions blood loss can be especially beneficial in tropical settings where the risk of viral transmission is high. The combined use of blood-sparing and autogenic transfusion techniques requires preoperative assessment of transfusion requirements. The expected amount of preoperative blood loss must be determined and compared with the acceptable amount of blood loss for the patient in function of transfusion threshold. Various techniques to reduce the need for autogenic blood transfusion can be used depending on locally available resources. Blood-sparing techniques include treatment to increase the patient's baseline hemoglobin rates, use of cell saving systems for autologous blood transfusion, and/or perioperative transfusion of recuperated blood. In this article these techniques are illustrated in two practical clinical cases.