How are human papillomavirus (HPV), cervical cancer, and the recently developed HPV vaccines associated with each other? Human papillomavirus is a highly prevalent infection that is easily and unknowingly transmitted because of its asymptomatic nature and long incubation period. Infection requires skin-to-skin contact and is typically sexually transmitted. More than one-half of sexually active women acquire HPV, making it the most prevalent sexually transmitted disease. Cervical cancer ranks second in deaths from cancer among women in developing countries and kills nearly 4000 women in the United States annually. Several types of HPV have been strongly linked to causing cervical cancer and genital warts. Those causing cervical cancer are considered high-risk types and those causing genital warts are considered low-risk types. Until recently, prevention strategies included abstinence, condom usage, and early detection with a Papanicolaou test (Pap smear). New developments have led to 2 vaccines aimed at preventing the viral infection. One is a quadrivalent vaccine preventing infection from 4 HPV types (HPV types 6, 11, 16, and 18) (Gardasil). It is approved in the United States and Europe for the prevention of HPV-associated cervical cancers and genital warts in females between the ages of 9 and 26 years old. The second is a bivalent vaccine preventing infection from 2 high-risk oncogenic HPV types (HPV types 16 and 18) (Cervarix). It is currently under study and not yet available in the United States. Both vaccines have proven highly effective at preventing infection from their corresponding HPV types. Of importance, neither vaccine is to be used for treatment. Vaccination does not replace routine cervical cancer screening with Pap smears, as the vaccines do not protect against all HPV types.

Atrioventricular (AV) block in pregnancy is infrequently encountered and there is little management guidance available. We present a case of a 24-year-old G3P1011 at 24 weeks' gestation who presented to the obstetrics and gynecology clinic complaining of palpitations, fatigue, and dyspnea on exertion. Cardiology workup including an electrocardiogram (ECG) and Holter monitor detected second-degree type II (Mobitz) AV block with the longest asystole event lasting 15.8 seconds. A St. Jude's dual-chamber pacemaker (Abbott Laboratories, Abbott Park, IL) was implanted immediately. Standard radiation precautions were taken with additional shielding for the fetus. The patient experienced significant improvement in her symptoms. The patient went into labor at 37 3/7 weeks. Due to non-reassuring fetal heart tones, a cesarean section was performed, and a healthy baby girl was born. The management of heart block in pregnancy can be divided into involving those who are symptomatic and those who are asymptomatic. Symptoms of heart block can include palpitations, fatigue, dyspnea, and/or syncope; the presence of these symptoms warrants the placement of a pacemaker, preferably during pre-pregnancy or during the first two trimesters, as high-grade heart block is associated with significant mortality. Those who are in their last trimester or postpartum should consider the use of a temporary pacemaker as heart block could be due to pregnancy-related cardiovascular changes. For women with heart block, labor and delivery could result in worsening of bradycardia due to uterine contractions displacing blood into the central circulation. Most women with heart block do well in labor and delivery and having a pacemaker is not necessarily an indication for a cesarean section.

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The Covering Tour Problem finds application in distribution network design. It includes two types of vertices: the covering ones and the ones to be covered. This problem is about identifying a lowest-cost Hamiltonian cycle over a subset of the covering vertices in such a way that every element not of this type is covered. In this case, a vertex is considered covered when it is located within a given distance from a vertex in the tour. This paper presents a solution procedure based on a Selector operator that allows to convert a giant tour into an optimal CTP solution. This operator is embedded in an adaptive large neighborhood search. The method is competitive as shown by the quality of results evaluated using the output of a state-of-the-art exact algorithm.

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