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This study pioneers the feasibility of cost-effective partial nitritation/anammox (PN/A) in packed-bed trickling filters (TFs). Three parallel TFs tested different carrier materials, the presence or absence of bottom ventilation openings, hydraulic loading rates (HLR, 0.4-2.2 m 3 m -2 h -1 ), and free ammonia (FA) levels on synthetic medium. The inexpensive Argex expanded clay was recommended due to the similar nitrogen removal rates as commercially used plastics. Top-only ventilation at an optimum HLR of 1.8 m 3 m -2 h -1 could remove approximately 60% of the total nitrogen load (i.e., 300 mg N L -1 d -1 , 30 °C) and achieve relatively low NO 3 - -N accumulation (13%). Likely FA levels of around 1.3-3.2 mg N L -1 suppressed nitratation. Most of the total nitrogen removal took place in the upper third of the reactor, where anammox activity was highest. Provided further optimizations, the results demonstrated TFs are suitable for low-energy shortcut nitrogen removal., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Annually, the EU produces more than 100 million tonnes of urban biowaste, which is largely under-valorized and in some cases even still landfilled without any energy or material recovery. If Europe wants to be ready for the future, it will need to make better use of this large biomass potential within a circular economy approach. The research project funded by the European Commission under the Horizon 2020 programme entitled 'VOLATILE-Biowaste derived volatile fatty acid platform for biopolymers, bioactive compounds and chemical building blocks' aimed to produce volatile fatty acids (VFAs) from biowaste for reprocessing into products, materials or substances to close the material loop. During the project, the partners were able to obtain average volatile fatty acid yields of 627 g COD/kg organic matter (OM) for food waste, 448 g COD/kg OM for separately collected vegetable, garden and fruit waste (VGF) and 384 g COD/kg OM for the organic fraction of municipal solid waste (OF-MSW) at concentrations ranging from 12 to 48 g/L, 6 to 40 g/L and 13 to 26 g/L, respectively. A membrane filtration cascade consisting of micro-, ultra- and nano-filtration followed by reverse osmosis was identified as a feasible way to purify and concentrate the VFA effluent, making them a suitable carbon source for further fermentation processes. Besides technical optimization, socio-economic and legal aspects associated with this platform technology were also studied and show that although this technology is still in development, it is providing an answer to changing societal and market expectations both regarding organic waste treatment and bio-based production strategies. Based on the current technological, economic and market evolutions, it is expected that the VFAP will play an important role in organic waste treatment in the coming years., (© The Author(s) 2021. Published by Oxford University Press on behalf of FEMS. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Energy-positive sewage treatment can be achieved by implementation of oxygen-limited autotrophic nitrification/denitrification (OLAND) in the main water line, as the latter does not require organic carbon and therefore allows maximum energy recovery through anaerobic digestion of organics. To test the feasibility of mainstream OLAND, the effect of a gradual temperature decrease from 29 to 15 °C and a chemical oxygen demand (COD)/N increase from 0 to 2 was tested in an OLAND rotating biological contactor operating at 55-60 mg NH₄(+)-N L(-1) and a hydraulic retention time of 1 h. Moreover, the effect of the operational conditions and feeding strategies on the reactor cycle balances, including NO and N₂O emissions were studied in detail. This study showed for the first time that total nitrogen removal rates of 0.5 g N L(-1) day(-1) can be maintained when decreasing the temperature from 29 to 15 °C and when low nitrogen concentration and moderate COD levels are treated. Nitrite accumulation together with elevated NO and N₂O emissions (5% of N load) were needed to favor anammox compared with nitratation at low free ammonia (<0.25 mg N L(-1)), low free nitrous acid (<0.9 μg N L(-1)), and higher DO levels (3-4 mg O₂ L(-1)). Although the total nitrogen removal rates showed potential, the accumulation of nitrite and nitrate resulted in lower nitrogen removal efficiencies (around 40%), which should be improved in the future. Moreover, a balance should be found in the future between the increased NO and N₂O emissions and a decreased energy consumption to justify OLAND mainstream treatment.

Purpose: Essential blepharospasm can be associated with apraxia of eyelid opening and is characterized by the inability to initiate the act of eyelid elevation even after cessation of orbicularis spasms. Current therapies such as botulinum toxin injections, orbicularis resection, or neurectomy may be unsuccessful or have undesired side effects., Methods: Frontalis suspension was used to treat 13 consecutive patients with apraxia and blepharospasm during a 4-year interval. Follow-up ranged from 16 months to 55 months. To improve the aesthetic outcome, an upper blepharoplasty was done at the same time as the frontalis suspension in 7 cases., Results: Good or excellent functional results were obtained in 10 of 13 patients. In 6 of these patients, the spasm disappeared completely. Therapy was unsuccessful in 1 patient, and in 2 patients blepharospasm recurred after 9 months., Conclusion: Patients with blepharospasm and apraxia of eyelid opening may benefit from a frontalis suspension operation, which can be considered minimally invasive and reversible.

We describe the surgical approach of two patients with myogenic blepharoptosis. The ptosis is caused by a glycogenosis type II (Pompe disease) in the first case and is due to a juvenile, chronic progressive external ophthalmoplegia (Kearns-Sayre syndrome) in the second case. The first patient presented a unilateral ptosis. The ptosis in the second patient was bilateral and manifest. The eyelids could only be opened manually. A resection of the palpebral levator muscle was carried out under local anesthesia. The choice of the technique will be explained. The amount of levator resection was calculated considering the residual eyelid motility and Bell's phenomenon. Electronmicroscopy of the resected levator muscle will be discussed.

A frontalis suspension was carried out in a patient with an essential type of blepharospasm, characterized by difficulties in initiating the act of lid elevation, often referred to as the apractic form of blepharospasm or, as J. Elston proposed, the pretarsal blepharospasm. The patient tries to open the eyes by using the frontalis muscle or by manual traction. It is known than in this form of blepharospasm, insufficient results are seen after botulinum toxin infection. Proper examination of the skin crease of the upper eyelid and of the eyelid gives an idea of the insertion of the levator aponeurosis and of the levator muscle function. A desinsertion, due to frequent manual traction, may be found. In this case, reinsertion of the aponeurosis may relieve the symptoms. If no desinsertion is present a frontalis suspension, similar to those used in ptosis surgery, may give good results.

A 63 years old woman presented with bilateral blepharospasms and eyelid apraxia which was treated with Botulinum toxin injections. A post-treatment ptosis was seen with preserved levator function. It was then suggested that manual eyelid traction could have caused aponeurotic dehiscence of the levator muscles. Surgical exploration confirmed this diagnosis. One must be aware that eyelid apraxia can mask an aponeurotic dehiscence of the levator muscle induced by chronic manual traction exerted on the apractic eyelids.

Rabbit retinas were treated with laser coagulations of low intensity, using five different wavelengths. After coagulation (1, 4 and 28 days), the retinas were stained for GABA, using a direct biotin-avidin-horseradish peroxidase immunocytochemical method. These time intervals were chosen with regard to the existing knowledge of retinal repair. The staining for GABA was increased in the inner plexiform layer at the centre of the lesions at days 1 and 4 after coagulation. At the margins of the lesions, cells in the ganglion cell layer showed strong staining and cells in the amacrine cell layer showed cuffing, independent of the wavelength used. On day 28, a regression of the hyperstaining was noted. Some possible pathophysiological mechanisms are discussed.

Rabbit retinas were treated with low-intensity laser coagulation at five different wavelengths. Using an indirect immunocytochemical method, the retinas were stained for glial fibrillary acidic protein (GFAP) at 2, 4, 21 and 32 days after coagulation such that we could follow GFAP expression in the Müller cells during retinal repair. GFAP-positive staining was found in the end feet of the Müller cells at 2 days after laser coagulation. GFAP immunoreactivity was observed throughout the Müller cells, surrounding the central necrotic tissue, at days 4, 21 and 32 after laser coagulation. Scar tissue in the subretinal space at days 21 and 32, which was more pronounced for the longer wavelengths produced by the Krypton and Nd-YAG lasers, also showed GFAP immunoreactivity. The Müller cells remained GFAP-immunoreactive for at least 32 days after laser coagulation.

The clinical manifestations of rheumatic diseases have been studied in a population of 440 HLA-B27-positive patients. Fifty-eight per cent had peripheral joint involvement. After statistical analysis and clustering of characteristics, three patterns of peripheral joint involvement were found. They were referred to as the X, Y and Z type for mnemotechnical reasons. The X type includes male patients with sacroiliitis, spondylitis, uveitis and uni- or bilateral arthritis of hip and/or shoulder. Y type patients present sacroiliitis, pauci-articular asymmetrical joint involvement and tendinitis. Z type patients are characterized by sacroiliitis, polyarticular symmetrical joint involvement and a positive IgM rheumatoid factor. This classification enables a new approach to the pathology, diagnosis and therapy of the seronegative spondyloarthropathies.

Experimental study of the intraocular penetration of six drugs with therapeutic effect on toxoplasma. A direct and an indirect method are used. The penetration of six drugs administered sub-conjunctival, retrobulbar and intramuscular in one shot is measured in the anterior chamber, the vitreous and the retina-choroid of a healthy rabbit eye. The best results are obtained for: spiramycin, trimethoprim-sulfamethoxazole and clindamycin. The therapeutic efficiency of four drugs on infected rabbit eyes with toxoplasma are studied using an indirect method: pyrimethamine and especially doxycycline have a positive effect.

The value of a carotid endarterectomy in patients with ocular symptoms such as amaurosis fugax, scotoma, loss of visual acuity or diplopia is considered from an ophthalmological point of view. The concurrent fundus lesions are discussed and the ocular results of two different groups of patients are presented. A first group of 12 patients underwent an endarterectomy for their specific ocular complaints, while a second group of 15 patients with ocular symptoms associated with carotid lesions were treated conservatively. The usefulness of the retro-ocular doppler sonography in the vascular check-up is stressed. A good visual prognosis after carotid endarterectomy can be predicted when the blood velocity in the ophthalmic artery is 0.2 to 0.4 m/sec.

This case was previously reported in 1973 at the 46th annual general scientific meeting of this College. Following a suggestion made at the meeting the patient was referred for radiotherapy, with a result so satisfactory as to call for a restatement of the case.

A uniform method of recording data on head and neck cancer patients is presented. This has been shown to work well in the clinical field. The records are always completely up to date and immediately available at any time for data analysis.