On the social (sub)optimality of divisionalization under product differentiation

We revisit the interplay between differentiation and divisionalization in a duopoly version of Ziss (Econ Lett 59:133\u2013138, 1998). We model divisionalization as a discrete problem to prove that (i) firms may choose not to become multidivisional; and (ii) there may arise asymmetric outcomes in mixed strategies, due to the existence of multiple symmetric equilibria. If industry-wide divisionalization is the unique equilibrium, it can be socially efficient provided goods are almost perfect substitutes. Even small degrees of differentiation may suffice to make industry-wide divisionalization socially desirable because of the prevalence of consumers\u2019 taste for variety over the replication of fixed costs

Adenotonsillectomy in children with recurrent acute tonsillitis: review and implications for practice

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VOICe THeRApy FOR LARyNgeAL HeMIpLegIA: THe ROLe OF TIMINg OF INITIATION OF THeRApy

Objective: Laryngeal hemiplegia, also known as vocal fold paralysis, causes severe communicative disability. Although voice therapy is commonly considered to be beneficial for improving the voice quality in several voice disorders, there are only a few papers that present scientific evidence of the effectiveness of voice therapy in treating the disabilities of laryngeal hemiplegia. The aim of this study was to evaluate the outcomes of voice therapy in patients with laryngeal hemiplegia and to evaluate the role of the time gap between onset of laryngeal hemiplegia and initiation of therapy. Design: A prospective study comparing subjects treated either within or more than 3 months after the onset of laryngeal hemiplegia. Subjects: The study involved 30 laryngeal patients with hemiplegia (16 males, 14 females, age range 15–80 years). Methods: All patients underwent videolaryngostroboscopy, maximum phonation time measurement, GIRBAS perceptual evaluation, Voice Handicap Index self-assessment and Multi-Dimensional Voice Program voice analysis before and after therapy. Results: In all tests, there were significant improvements in voice quality, both in the group treated within 3 months after the onset of laryngeal hemiplegia and in the group treated after this time. Conclusion: Voice therapy is effective in treating laryn geal hemiplegia even if treatment is delayed by more than 3 months from onset of laryngeal hemiplegia

A Library Approach to the Development of BenzaPhos, Highly Efficient Chiral Supramolecular Ligands for Asymmetric Hydrogenation

A library of chiral supramolecular ligands named BenzaPhos, of straightforward preparation (two steps from commercial or readily available starting materials) and modular structure, was designed and synthesized. The ligands were screened in the search of new rhodium catalysts for the enantioselective hydrogenation of several benchmark and industrially relevant substrates. Once a series of hits were identified, structural modifications were introduced on three of the best ligands and a small second-generation library was created. Members of the latter showed outstanding levels of activity and enantioselectivity in the hydrogenation of challenging olefins such as enamide S4 and beta-dehydroamino ester S5 (> 99% ee: best value ever reported in both cases). A series of control experiments were undertaken in order to clarify the role of hydrogen bonding in determining the catalytic properties of the new ligands. The results of these experiments, together with those of computational studies carried out on four dihydride complexes involved in the catalytic hydrogenation of substrate S4, strongly suggest that a substrate orientation takes place in the catalytic cycle by formation of a hydrogen bond between the ligand amide oxygen and the substrate amide NH

Autologous fat injection to face and neck: from soft tissue augmentation to regenerative medicine

Minimally-invasive autologous fat injection of the head and neck region can be considered a valid alternative to major invasive surgical procedures both for aesthetic and functional purposes. The favourable outcomes of autologous fat injection in otolaryngological practice are due to the filling of soft tissue and, mainly, to the potential regenerative effect of adipose-derived mesenchymal stem cells. Herewith, some important biological preliminary remarks are described underlying the potential of autologous fat injection in regenerative medicine, and personal experience in using it for both consolidated clinical applications, such as fat grafting to the face and vocal fold augmentation in the treatment of glottic incompetence, and more recent applications including the treatment of post-parotidectomy Frey syndrome and velopharyngeal insufficiency

Riding the Wave of Monodentate Ligand Revival : from the A/B Concept to Noncovalent Interactions

The rediscovery of chiral monodentate ligands made in the period 1999\u20132003 had important consequences in enantioselective transition-metal catalysis, such as the introduction of the A/B concept (i.e., use of monodentate ligand mixtures) and, later, a renewed interest in supramolecular ligands capable of ligand\u2013ligand and ligand\u2013substrate interactions. This Personal Account summarizes the contributions made by our research group in this area in the period 2004\u20132015, which reflect the abovementioned developments. Within this area, we introduced some original concepts, such as 1) the use of chiral tropos ligand mixtures; 2) the development of new strategies to maximize heterocomplex formation from combinations of simple monodentate ligands; 3) the investigation of new ligand\u2013ligand interactions to achieve selective heterocomplex formation; and 4) the development of highly efficient and synthetically accessible supramolecular ligands

The velo-uvulo-pharyngeal lift or "roman blinds" technique for treatment of snoring: a preliminary report

Snoring is caused by vibrating anatomical structures in the upper aerodigestive tract. It can be treated surgically and non-surgically, although resective procedures are associated with high postoperative morbidity and failure rate. We describe a new non-resective surgical procedure called the velo-uvulo-pharyngeal lift in which the soft palate is lifted, shortened, advanced and stiffened by means of permanent threads anchored to fibro-osseous attachments at the level of the posterior nasal spine and both pterygoid hamuli. Four adult patients (median age 44.5 years; range 42-65) affected by snoring and mild obstructive sleep apnoea-hypopnoea syndrome (apneoa-hypopnoea index, AHI < 20) requiring septal surgery under general anesthesia also underwent velo-uvulo-pharyngeal lift. There were no significant intra- or post-operative complications, and all of the patients reported immediate snoring relief. The main complaints were slight pain and a sensation of local fullness, both of which spontaneously disappeared within two days. The subjective clinical improvement in snoring was confirmed during post-operative follow-up (median 15.5 months; range 6-25), as was the stable reshaping of the soft velo-uvulo-pharyngeal tissues and enlargement of the mesopharyngeal space. There was also a decrease in daytime sleepiness. Our preliminary results suggest that velo-uvulo-pharyngeal lift is a simple, cost-effective and minimally invasive means of widening the mesopharyngeal space in snoring patients with or without mild sleep apnoea-hypopnoea syndrome. The widening of the mesopharyngeal space prevents contact-induced wall vibrations and its inspiratory obstruction causing hypopnoea and apnoea. It can also be combined with other procedures if indicated

The hypoxia sensitive metal transcription factor MTF-1 activates NCX1 brain promoter and participates in remote postconditioning neuroprotection in stroke

Remote limb ischemic postconditioning (RLIP) is an experimental strategy in which short femoral artery ischemia reduces brain damage induced by a previous harmful ischemic insult. Ionic homeostasis maintenance in the CNS seems to play a relevant role in mediating RLIP neuroprotection and among the effectors, the sodium-calcium exchanger 1 (NCX1) may give an important contribution, being expressed in all CNS cells involved in brain ischemic pathophysiology. The aim of this work was to investigate whether the metal responsive transcription factor 1 (MTF-1), an important hypoxia sensitive transcription factor, may (i) interact and regulate NCX1, and (ii) play a role in the neuroprotective effect mediated by RLIP through NCX1 activation. Here we demonstrated that in brain ischemia induced by transient middle cerebral occlusion (tMCAO), MTF-1 is triggered by a subsequent temporary femoral artery occlusion (FAO) and represents a mediator of endogenous neuroprotection. More importantly, we showed that MTF-1 translocates to the nucleus where it binds the metal responsive element (MRE) located at −23/−17 bp of Ncx1 brain promoter thus activating its transcription and inducing an upregulation of NCX1 that has been demonstrated to be neuroprotective. Furthermore, RLIP restored MTF-1 and NCX1 protein levels in the ischemic rat brain cortex and the silencing of MTF-1 prevented the increase of NCX1 observed in RLIP protected rats, thus demonstrating a direct regulation of NCX1 by MTF-1 in the ischemic cortex of rat exposed to tMCAO followed by FAO. Moreover, silencing of MTF-1 significantly reduced the neuroprotective effect elicited by RLIP as demonstrated by the enlargement of brain infarct volume observed in rats subjected to RLIP and treated with MTF-1 silencing. Overall, MTF-dependent activation of NCX1 and their upregulation elicited by RLIP, besides unraveling a new molecular pathway of neuroprotection during brain ischemia, might represent an additional mechanism to intervene in stroke pathophysiology

Rhodium-catalyzed asymmetric hydrogenation of olefins with PhthalaPhos, a new class of chiral supramolecular ligands

A library of 19 binol-derived chiral monophosphites that contain a phthalic acid diamide group (Phthala- Phos) has been designed and synthesized in four steps. These new ligands were screened in the rhodium-catalyzed enantioselective hydrogenation of prochiral dehydroamino esters and enamides. Several members of the library showed excellent enantioselectivity with methyl 2-acetamido acrylate (6 ligands gave >97% ee), methyl (Z)-2- acetamido cinnamate (6 ligands gave >94% ee), and N-(1-phenylvinyl)acetamide (9 ligands gave >95% ee), whilst only a few representatives afforded high enantioselectivities for challenging and industrially relevant substrates N-(3,4-dihydronaphthalen-1- yl)-acetamide (96% ee in one case) and methyl (E)-2-(acetamidomethyl)-3- phenylacrylate (99% ee in one case). In most cases, the new ligands were more active and more stereoselective than their structurally related monodentate phosphites (which are devoid of functional groups that are capable of hydrogen-bonding interactions). Control experiments and kinetic studies were carried out that allowed us to demonstrate that hydrogen-bonding interactions involving the diamide group of the PhthalaPhos ligands strongly contribute to their outstanding catalytic properties. Computational studies carried out on a rhodium precatalyst and on a conceivable intermediate in the hydrogenation catalytic cycle shed some light on the role played by hydrogen bonding, which is likely to act in a substrate-orientation effect. \ua9 2012 Wiley-VCH Verlag GmbH&Co. KGaA, Weinheim

Review of Systemic Antibiotic Treatments in Children with Rhinosinusitis

Antibiotic treatment in paediatric rhinosinusitis is still a matter of debate, as the current guidelines have been drafted mainly based on clinical studies published before 2013. Recent modifications in the epidemiological basis of the disease might mean that current treatments are not completely adequate considering the evolving microbiological profile of the disease. The present paper reviews the role of systemic antibiotics in children with acute (ARS), chronic (CRS), recurrent (RARS), and complicated acute (CoARS) rhinosinusitis. A total of 14 studies (including 3 prospective non-randomised studies, 8 retrospective studies, and 3 prospective randomised studies) of the 115 initially identified papers were included in this review, corresponding to 13,425 patients. Five papers dealt with ARS, four papers with RARS or CRS, and five papers with CoARS; the remaining papers included patients with either ARS or CRS. Data about the effectiveness of antibiotic treatment in children with ARC, CRS, and CoARS is scarce, as only three randomised controlled trials have been published in the last decade, with contrasting results. There is an urgent need for dedicated controlled trials not only to test the actual clinical benefits deriving from the routine use of systemic antibiotics in different categories of patients but also to compare the effectiveness of various therapeutic protocols in terms of the type of antibacterial molecules and the duration of treatment