Around the tangent cone theorem

A cornerstone of the theory of cohomology jump loci is the Tangent Cone theorem, which relates the behavior around the origin of the characteristic and resonance varieties of a space. We revisit this theorem, in both the algebraic setting provided by cdga models, and in the topological setting provided by fundamental groups and cohomology rings. The general theory is illustrated with several classes of examples from geometry and topology: smooth quasi-projective varieties, complex hyperplane arrangements and their Milnor fibers, configuration spaces, and elliptic arrangements.Comment: 39 pages; to appear in the proceedings of the Configurations Spaces Conference (Cortona 2014), Springer INdAM serie

Splenic rupture as the presenting manifestation of primary splenic angiosarcoma in a teenage woman: a case report

<p>Abstract</p> <p>Introduction</p> <p>Primary splenic angiosarcoma is a rare neoplasm of vascular origin carrying a very poor prognosis, partly due to its high metastatic potential. This disease presents frequently with splenic rupture and hemorrhage. We report the case of a 17-year-old woman who presented with rupture of a primary splenic angiosarcoma.</p> <p>Case presentation</p> <p>The patient presented with diffuse abdominal pain and distention. Clinical examination revealed severe tenderness in the left upper abdominal quadrant, a palpable abdominal mass, and hemodynamic instability with a systolic arterial blood pressure of 75 mmHg and heart rate of 135 beats per minute. Blood tests revealed anemia (hemoglobin 7.0 g/dl) and thrombocytopenia (platelets 70 × 10⁹/liter). After initial fluid resuscitation and stabilization, abdominal ultrasound and computed tomography were performed, revealing a large quantity of intraperitoneal free fluid, an enlarged spleen, and a heterogeneous low-density signal within the splenic parenchyma, which showed varying degrees of contrast enhancement. At laparotomy a huge (weight 1530 g, diameter 19 cm) actively bleeding spleen was identified and splenectomy was performed. Histopathology showed a primary splenic angiosarcoma. After an uneventful recovery, the patient was discharged on the sixth postoperative day.</p> <p>Conclusion</p> <p>Primary splenic angiosarcoma is rare. Although this malignancy is usually encountered in advanced age, there have been a few reported cases among younger patients. The case reported here presented with splenic rupture, was treated by laparotomy and splenectomy, and the patient is disease free 16 months after surgery.</p

Central Sleep Apnea

Obstructive sleep apnea syndrome (OSAS) is the most common organic disorder of excessive daytime somnolence. In cross-sectional studies the minimum prevalence of OSAS among adult men is about one per cent. Prevalence is highest among men aged 40-65 years. The highest figures for this age group indicate that their prevalence of clinically significant OSAS may be 8.5% or higher. Habitual snoring is the most common symptom of OSAS (70-95%). The most significant risk factor for OSAS is obesity, especially upper body obesity. Other risk factors for snoring, and for OSAS, are male gender, age between 40 and 65 years, cigarette smoking, use of alcohol, and poor physical fitness

Efficacy of Repeated Intraperitoneal Administration of Levobupivacaine in Pain and Opioid Consumption after Elective Laparoscopic Cholecystectomy: A Prospective Randomized Placebo-controlled Trial

Purpose: To estimate the effect of intraperitoneal levobupivacaine on postoperative pain and analgesic requirements, during the first 24 hours after elective laparoscopic cholecystectomy (LC). Materials and Methods: In this prospective, randomized, placebo-controlled study, 73 consecutive patients scheduled for LC were randomized into 2 groups. In the local anesthetic group 36 patients received 10 mL of 0.5% levobupivacaine intraperitoneally at the end of the LC and at 4 hours postoperatively, whereas in the placebo group 37 patients received 10 mL of 0.9% normal saline. Visual analog scale pain scores, analgesic consumption, side-effects, and vital signs were recorded for 24 hours postoperatively. Results: In the local anesthetic group lower visual analog scale pain scores were observed postoperatively, both at rest and at movement (P-values compared with placebo, 0.012 and &lt;0.001, respectively). Fentanyl consumption was greater in the placebo group (P-value &lt;0.001). Conclusions: Intraperitoneal administration of 10 mL 0.5% levobupivacaine after LC is effective in reducing postoperative pain and decreasing opioid consumption. © 2016 Wolters Kluwer Health, Inc. All rights reserved