An algorithm for constructing certain differential operators in positive characteristic

Given a non-zero polynomial $f$ in a polynomial ring $R$ with coefficients in a finite field of prime characteristic $p$, we present an algorithm to compute a differential operator $\delta$ which raises $1/f$ to its $p$th power. For some specific families of polynomials, we also study the level of such a differential operator $\delta$, i.e., the least integer $e$ such that $\delta$ is $R^{p^e}$-linear. In particular, we obtain a characterization of supersingular elliptic curves in terms of the level of the associated differential operator.Comment: 23 pages. Comments are welcom

Multidisciplinary Approach in a 12-Year-Old Patient Affected by Severe Obstructive Sleep Apnea: a Case-Report

A 12-year-old boy shows a restless sleep and snoring episodes declaring himself tired during the day and the school lessons. On clinical examination the patient presents a second-class profile, a retrusive jaw with a small chin and an open nasolabial angle. From the intraoral examination a tonsillar hypertrophy is denoted. The patient is sent by the ear, nose, and throat specialist (ENT) and subsequently subjected to a polysomnography (PSG). The ENT decides to subject him to a tonsillectomy and the subsequent PSG shows an improvement in the obstructive sleep apnea syndrome (OSAS) pathology with an apnea-hypopnea index (AHI) improved from 25.5 episodes/hr to 3.4 episodes/hr. Subsequently a orthodontic treatment with twin-block was start to further reduce the apnea episodes. The last PSG highlights the success of the treatment further lowering the AHI to 0.7 episodes/hr. This case report shows how a multidisciplinary approach to OSAS is fundamental also in the young patient and that the orthodontist carried out in this area a fundamental task both in diagnosis and treatment

Resolution of a Severe Grade of Obstructive Sleep Apnea Syndrome with Mandibular Advancement Device: A Case Report

Obstructive sleep apnea syndrome (OSAS) is a disorder of the sleep with episodes of the obstruction at the upper airway that can be recurrent, partial or complete. The continuous positive airway pressure (CPAP) is the gold treatment for OSAS, but many patients do not tolerate this kind of treatment, and for this reason mandibular advancement device are used. A 55-year-old Caucasian man affected by severe OSAS [apnea-hypopnea index (AHI): 51, lowest saturation value (NADIR): 77%] came at Padua University Hospital Dental Clinic after ENT evaluation to consider an alternative treatment to CPAP. After a surgery treatment and the use of oral appliance (Somnodent, Somnomed Limited) associated with vertical elastics AHI improve to 2.4 and NADIR to 88%

Elongated styloid process : an epidemiological study on digital panoramic radiographs

The styloid process is a projecton of the temporal bone, its lenght is between 20 to 30 mm, when it is longer than 30 mm it is defined elongated styloid process. The aim of this study is an epidemiological evaluation of 1003 digital panoramic radiographs in an Italian population between 5 and 90 years old. This is a retrospective analysis and the radiographs were selected from the Complex Operating Unit of Dentistry of Padua University Hospital database. The radiographs were performed using a Sirona Ortophos XG and the styloid process length was measured using the measuring tool of Sidexis Software. It was measured from the point where it left the temporal bone plate to its tip. Styloid processes measuring more than 30 mm were considered elongated. Chi-squared test, Fligner-Killeen test, Shapiro-Wilk test and t-test with Welch correction were performed. In the study 33.40% of the patients showed an elongated styloid process. The number of patients with elongated styloid process and the mean length of the process increase with the age confirming the chronic development of the calcification described in literature. No statistically significant correlation is found between the presence of elongated styloid process and the gender and affected side (bilateral or unilateral)

Dental water jet efficacy in the plaque control of orthodontic patients wearing fixed appliance : a randomized controlled trial

Different studies assess the role of fixed orthodontic appliances in supragingival plaque accumulation. In patients wearing fixed orthodontic appliances a good management of oral hygiene is required in order to prevent complication like as decay, enamel demineralization, gingivitis, gingival hyperplasia and periodontitis. The aim of this Randomized Controlled Trial (RCT) is to evaluate the efficacy of the use of a DWJ in patients under orthodontic treatment with fixed multibracket appliance. The study design was single-blinded RCT with a split mouth protocol. Each patient followed a personal cleaning protocol using a DWJ in addition to traditional brushing only on one side while just brushing on the control side. The side on which was decided to use the DWJ was chosen randomly and the dental hygienist who took the measurements was blind. Plaque and gingival indexes were evaluated at baseline and at one, three and six-months follow-up. It did not emerge any difference in the plaque and gingival indexes trend between the two groups. Patients initially reported an worsening of the indexes at one month evaluation, then they set at baseline levels at three and six months. The dental water jet does not improve significantly the efficacy of home oral hygiene in orthodontic patients wearing a multi-bracket fixed appliance. Patients did not show the traditional worsening during the whole orthodontic therapy

Elongated styloid process evaluation on digital panoramic radiograph in a North Italian population

The aim of this study is to evaluate the prevalence of elongated styloid process in digital panoramic radiographs in a North Italian population in relation to age, gender and side. This study was performed as a retrospective analysis on digital panoramic radiographs of 600 (271 males and 329 females) Italian patients between 6 and 87 years old. The styloid process length were measured using the measuring tool of Sidexis Software. It was measured from the point where it left the temporal bone plate to its tip. Styloid processes measuring more than 30 mm were considered elongated. Chi-squared and Fisher tests were used and the test is considered significant if the p-value is lower or equal to 0.05. Thirty-three per cent of the patients showed an elongated styloid process. Seventeen per cent were elongated on both right and left side, fifteen point nine per cent were elongated only in one side. The prevalence of elongated styloid process was high and a progressive increase of the elongation prevalence was found in older groups

An unusual case of bowel obstruction in emergency surgery: The heterotopic mesenteric ossification

The heterotopic mesenteric ossification, also known as myositis ossificans, is a rare form of heterotopic ossification, a metaplastic phenomenon where new bone is formed in the mesenteric base, generally after abdominal trauma (surgical or other). The pathophysiology of heterotopic mesenteric ossification is unknown; clinical presentation is not specific, with vague abdominal symptoms, uncertain radiological findings, and often regular laboratory exams. No consensus exists on the best possible approach, although it might well be both medical and surgical. We reviewed the clinical history of a 28-year-old man with a recent motor vehicle accident who was admitted to our surgical unit with symptoms consistent with a small bowel obstruction; after surgery, a diagnosis of myositis ossificans was surprisingly made

Voltage control of magnetism with magneto-ionic approaches : beyond voltage-driven oxygen ion migration

Magneto-ionics is an emerging field in materials science where voltage is used as an energy-efficient means to tune magnetic properties, such as magnetization, coercive field, or exchange bias, by voltage-driven ion transport. We first discuss the emergence of magneto-ionics in the last decade, its core aspects, and key avenues of research. We also highlight recent progress in materials and approaches made during the past few years. We then focus on the "structural-ion"approach as developed in our research group in which the mobile ions are already present in the target material and discuss its potential advantages and challenges. Particular emphasis is given to the energetic and structural benefits of using nitrogen as the mobile ion, as well as on the unique manner in which ionic motion occurs in CoN and FeN systems. Extensions into patterned systems and textures to generate imprinted magnetic structures are also presented. Finally, we comment on the prospects and future directions of magneto-ionics and its potential for practical realizations in emerging fields, such as neuromorphic computing, magnetic random-access memory, or micro- and nano-electromechanical systems

Screening of bacterial endophytes as potential biocontrol agents against soybean diseases

Aims: This research was aimed at identifying and characterizing endophytic micro-organisms associated with soybean that have antimicrobial activity towards soybean pathogens. Methods and Results: Soybean plants were collected from field trials in four locations of southern Brazil that were cultivated with conventional (C) and transgenic glyphosate-resistant (GR) soybeans. Endophytic bacteria isolated from roots, stems and leaves of soybeans were evaluated for their capacity to inhibit fungal and bacterial plant pathogens and 13 micro-organisms were identified with antagonistic activity. Approximately 230 bacteria were isolated and identified based on the 16S rRNA and rpoN gene sequences. Bacteria isolated from conventional and transgenic soybeans were significantly different not only in population diversity but also in their antagonistic capacity. Thirteen isolates showed in vitro antagonism against Sclerotinia sclerotiorum, Phomopsis sojae and Rhizoctonia solani. Bacillus sp. and Burkholderia sp. were the most effective isolates in controlling bacterial and fungal pathogens in vitro. Extracts and precipitates from culture supernatants of isolates showed different patterns of inhibitory activity on growth of fungal and bacterial pathogens. Conclusions: Bacillus sp. and Burkholderia sp. were the most effective isolates in controlling fungal pathogens in vitro, and the activity is mainly due to peptides. However, most of the studied bacteria showed the presence of antimicrobial compounds in the culture supernatant, either peptides, bacteriocins or secondary metabolites. Significance and Impact of the Study: These results could be significant to develop tools for the biological control of soybean diseases. The work brought to the identification of micro-organisms such as Bacillus sp. and Burkholderia sp. that have the potential to protect crops in order to enhance a sustainable management system of crops. Furthermore, the study provides the first evidences of the influence of management as well as the genetics of glyphosate-resistant soybean on the diversity of bacterial endophytes of soybean phytobiome.Facultad de Ciencias Agrarias y Forestale