Variational reduced density matrix method in the doubly-occupied configuration interaction space using four-particle N-representability conditions: Application to the XXZ model of quantum magnetism.

This work deals with the variational determination of the two-particle reduced density matrix (2-RDM) and the energy corresponding to the ground state of N-particle systems within the doubly occupied configuration interaction (DOCI) space. Here, we impose for the first time up to four-particle N-representability constraint conditions in the variational determination of the 2-RDM matrix elements using the standard semidefinite programming algorithms. The energies and 2-RDMs obtained from this treatment and the corresponding computational costs are compared with those arisen from previously reported less restrictive variational methods [D. R. Alcoba et al., J. Chem. Phys. 149, 194105 (2018)] as well as with the exact DOCI values. We apply the different approximations to the one-dimensional XXZ model of quantum magnetism, which has a rich phase diagram with one critical phase and constitutes a stringent test for the method. The numerical results show the usefulness of our treatment to achieve a high degree of accuracy.

Benchmarking the Variational Reduced Density Matrix Theory in the Doubly Occupied Configuration Interaction Space with Integrable Pairing Models.

The variational reduced density matrix theory has been recently applied with great success to models within the truncated doubly occupied configuration interaction space, which corresponds to the seniority zero subspace. Conservation of the seniority quantum number restricts the Hamiltonians to be based on the SU(2) algebra. Among them there is a whole family of exactly solvable Richardson-Gaudin pairing Hamiltonians. We benchmark the variational theory against two different exactly solvable models, the Richardson-Gaudin-Kitaev and the reduced BCS Hamiltonians. We obtain exact numerical results for the so-called [Formula: see text] N-representability conditions in both cases for systems that go from 10 to 100 particles. However, when random single-particle energies as appropriate for small superconducting grains are considered, the exactness is lost but still a high accuracy is obtained.

[Neuronal dysplasia of the colon. A case report]. / Displasia neuronale del colon. Descrizione di un caso clinico.

A clinical case of Neuronal Intestinal Dysplasia (NID) is reported. This is an important pathology which is part of congenital alterations of bowel's innervation. This disease consists of two forms (A and B) which occur during different ages causing problems in intestinal motility with consequent various symptoms. Actually NID is diagnosed easier than in the past because histopathological techniques are very refined and permit to distinguish NID from cases once classified as Hirschsprung's disease. Histology can show an increase of Ach and Ldh activity in cholinergic fibers of lamina propria and of circular layer of intestinal wall. In this report a chronic status of constipation refractory to medical therapy has been treated with a total colectomy and an ileo-rectal anastomosis, resulting in a complete resolution of symptoms.

Altered expression of androgen-receptor isoforms in human colon-cancer tissues.

Many groups have examined of androgen the effects on normal and neoplastic colon tissues, but no clear picture has hitherto emerged. In particular, the presence and the function of the androgen receptor (AR) has only partially been investigated in the past. The present study reports analysis of expression of the AR gene as messenger RNA and as protein in surgical samples of neoplastic colon mucosa and of corresponding healthy surrounding tissue. Specific binding for DHT, demonstrating the presence of AR, was observed in almost all the samples (2 samples out of 12 were negative). No significant difference was observed between healthy and neoplastic mucosa, or between male and female patients. A further characterization of AR was performed with Western blot, using 2 different primary antibodies. Both AR isoforms, AR-B and AR-A, were detected in healthy mucosa, while only AR-A, resolving at 87 kDa, was observed in neoplastic mucosa. RT-PCR analysis revealed the transcript for AR in both healthy and neoplastic mucosa in 10 samples; no message was detectable in 2 samples (negative also for binding); 2 additional samples presented AR mRNA only in healthy colon mucosa, 2 others only in neoplastic mucosa. In addition, a variant AR messenger RNA, probabily derived from alternative splicing, was observed. We found that AR is expressed both in healthy and in neoplastic colon mucosa, either as mRNA or as protein. Neoplastic colon tissue shows a characteristic loss of expression of the AR-B isoform, while AR-A expression is maintained. These findings underscore the possible role of androgen and its receptor in colon carcinogenesis.

Adrenal location of the echinococcus. Considerations on a clinical case.

Adrenal location of a hydatic cyst is a clinical occurrence of exceptional rarity, especially in its primitive form and it could be evaluated, on the operative and autoptic comparison, not to exceed overall 0.5% of all the possible locations. Moreover, among all the cystic formations of the adrenal glands, parasitic ones are only 7%. Our observation of a case of adrenal hydatidosis, initially suspected as hepatic mass, was casually discovered by means of abdominal ultrasonography and later confirmed with the operation. This work contributes to the knowledge of this pathology, emphasizing diagnostic difficulties, and, considering the exiguous literature, helping us in supplying real indications to the surgical treatment.

[Extrahepatic gastrinoma. Report of a clinical case]. / Gastrinoma extrapancreatico. Descrizione di un caso clinico.

Gastrinoma is a rare neoplasia producing gastrina, the hormone responsible of the clinic manifestations related to Zollinger-Ellison syndrome. The localization of gastrinoma is pancreatic or extrapancreatic (usually in Stabile and Passaro triangle). We present a case report concerning an extra-pancreatic gastrinoma not localized in this area and included in a lymph node. This is an extremely infrequent localization (2.4%). There are two different opinions about this localization. Some authors think that this is always a secondary lesion of a small primary neoplasia usually asymptomatic. Other authors think that there are primary lymph nodal gastrinomas that could be safely removed with excision of lymph node. The infrequent localisation of this case induced us to report this experience in order to contribute to the comprehension of this pathology.

[Rehabilitation of deafness in the elderly: multidisciplinary intervention in experimental university center]. / La riabilitazione nella sordità dell'anziano: intervento multidisciplinare in un centro universitario sperimentale.

The loss of hearing abilities can be seen as a complex event because psychological discomfort and relational inhibitions interact and lead to behaviours and attitudes which are insidious and dangerous for the quality of life of the patient. The complexity of the psychological-organic inconvenience, such as impairement disability and handicap led to the testing of recovery patterns. In this specific context interventions coming from different fields sustained from a complex operative model where different professional competences and evaluation processes interact. Therapeutic interventions have been carried out by an audiologist, an audiometrist, a speech therapist, an audioprostethist and a psychologist, all sharing the obtaining of the same result. The role of the audiologist is simply clinical and concerns the knowledge of the entire process of rehabilitation through the use of a prosthesis. This process concerns the audiologist, who operates in close collaboration with the audiometrist and the audioprosthesist: it is therefore a therapeutic activity that is interested mainly in the prescription of the prosthesis and the restoring of the communicative function. The speech therapist and the psychologist carry their interventions through a relationship with the patient, which places the respect of the patient's personality before any other procedural and technical aspect. Therefore they pay attention more to ergonomic factors than to the hearing loss, through the obtaining of the patient's self-confidence and of a better general psychological situation. Therefore the main purpose of each intervention is to create a process of rehabilitation aimed at restoring the communicative functions and the individual motivation in trying to do so both in the domestic and in the social environment. The authors refer the experience and the informations put together during three years of research activity. The results of the therapeutic intervention have brought to the acceptance of the prosthesis help, the adaptation to amplification, the reduction of the subjective and relational uneasiness for the use of prosthesis, the use of the prosthesis, the reintroduction to the world of sounds, the restoring of levels of autonomy and of self-estime, the discover of eventual abilities, which had never been used or underestimated, the reactivation of more rewarding social relationships and the reduction of the conditions of dependency related to the hearing disability.

[Complications of the surgical treatment of hemorrhoids and its therapy]. / Le complicanze della terapia chirurgica delle emorroidi ed il loro trattamento.

Hemorrhoidal disease is a common problem in a proctological ambulatory. Surgery is the best therapy for fourth degree hemorrhoids and the complication rate is 10-20%: postoperative urinary retention etiology is unknown but it may be caused by dysfunction of bladder muscles in response to pain and by an excessive perioperative somministration of fluids; delayed hemorrhage (i.e., 7-10 days postoperative) needs an inpatient care and the treatment ranges from bedside and packing to hemorrhoid pedicle suture ligation in the operating room. Anal stenosis is most commonly a result of a prior improper hemorrhoidectomy: it may be mild, moderate or severe; V-Y and C-anoplasty are the best therapy, also for ectropion. Rubber band Ligation and Sclerotherapy are the most common treatment of internal hemorrhoids: external hemorrhoid trombosis and delayed hemorrage are frequent complications.

Extraction of impacted third molars. A longitudinal prospective study on factors that affect postoperative recovery.

A longitudinal prospective trial was carried out on 146 patients to evaluate which factors can have an effect on postoperative recovery after extraction of impacted third molars or wisdom teeth. The following factors were considered: (1) age, (2) sex, (3) smoking habits, (4) use of the birth control pill, (5) previous history of pericoronitis, (6) degree of difficulty of the extraction, (7) expertise of the surgeon, (8) length of surgery, and (9) antibiotic prophylaxis. The following results were obtained and statistically significant differences were noted with respect to the pain in the context of (1) sex-males noted more pain on the 1st and 3rd days (p < 0.05) compared with females; (2) expertise of the surgeon--patients treated by surgeons with considerable or average expertise reported less pain on the first and third days (p < 0.05) compared with patients treated by surgeons with little expertise; and (3) age--a direct correlation was noted between age and pain (p < 0.05).

Circulatory dynamics during dental operations in patients with heart transplants.

Twelve patients with heart transplants and who needed dental operations were studied. At the same time, a group of normal subjects was enrolled as control. Blood pressure and heart rate were recorded in all subjects when they sat in the chair, after 5 minutes of relaxation, 5 minutes after administration of local anesthetic, and immediately after each dental extraction or curettage. No statistically significant difference was found between the values recorded during the different situations and the basal values in transplanted patients. Conversely, in the normal subjects, the values recorded when they sat in the chair, at the end of curettage, and at the end of dental extractions were significantly different from the basal values. The slight and dulled cardiovascular reaction to stress in patients with heart transplants suggests that the management of these patients is relatively uncomplicated and certainly easier than treatment of subjects with heart disease.

Tranexamic acid as a mouthwash in anticoagulant-treated patients undergoing oral surgery. An alternative method to discontinuing anticoagulant therapy.

A double-blind randomized study was carried out to evaluate the clinical hemostatic effect of tranexamic acid mouthwash after dental extraction in 30 patients who received anticoagulant agents. Surgery was performed with a reduction in the level of anticoagulant therapy in the control group and with no change in the level of anticoagulant therapy in the group who received the tranexamic acid. After the extraction the surgical field was irrigated with a 5% solution of tranexamic acid in the group of 15 patients whose anticoagulant treatment had not been discontinued and with a placebo solution in the group of 15 patients for whom the anticoagulant therapy was reduced. Patients were instructed to rinse their mouths with 10 ml of the assigned solution for 2 minutes four times a day for 7 days. There was no significant difference between the two treatment groups in the bleeding incidence after oral surgery. We conclude that the anticoagulant treatment does not need to be withdrawn before oral surgery provided that local antifibrinolytic therapy is instituted.

[Clinical evaluation of anesthesia using iontophoresis for pain control during scaling]. / Valutazione clinica dell'anestesia mediante ionoforesi nel controllo del dolore durante detartrasi.

A double blind study, cross-over in the same subjects compares the clinical efficacy of anesthetic application with iontophoresis versus placebo in the control of pain during scaling. None of ten subjects reported pain during scaling after iontophoresis with anesthetic, while six of ten reported pain after iontophoresis with placebo.

[Clinical experience with the Infrared Coagulator in the treatment of benign lesions of the oral cavity]. / Esperienza clinica con l'Infrared Coagulator nel trattamento delle lesioni benigne nel cavo orale.

The clinical efficacy of a new medico-surgical device was tested in the treatment of benign lesions of the oral cavity. The Infrared Coagulator was proved to be useful both in terms of reduced bleeding during operations and due to the satisfactory long-term healing of the wound.

[Palatine torus. Clinical picture and etiopathology]. / Il toro palatino. Eziopatogenesi e clinica.

In this note the Author deals with the so-called "torus palatinus", namely a hyperostosis, which develops very slowly, set on the median line of the palate; it usually develops during the years of youth and doesn't normally require surgical treatment because, as soon as it settles, it will not grow any more. Its surgical removal is needed only in some rare cases, when it does not allow the placing of a prothesis or when the mucosa covering it undergoes ulcerous pathology.