Geometric Phases, Symmetries of Dynamical Invariants, and Exact Solution of the Schr\"odinger Equation

We introduce the notion of the geometrically equivalent quantum systems (GEQS) as quantum systems that lead to the same geometric phases for a given complete set of initial state vectors. We give a characterization of the GEQS. These systems have a common dynamical invariant, and their Hamiltonians and evolution operators are related by symmetry transformations of the invariant. If the invariant is $T$-periodic, the corresponding class of GEQS includes a system with a $T$-periodic Hamiltonian. We apply our general results to study the classes of GEQS that include a system with a cranked Hamiltonian $H(t)=e^{-iKt}H_0e^{iKt}$. We show that the cranking operator $K$ also belongs to this class. Hence, in spite of the fact that it is time-independent, it leads to nontrivial cyclic evolutions and geometric phases. Our analysis allows for an explicit construction of a complete set of nonstationary cyclic states of any time-independent simple harmonic oscillator. The period of these cyclic states is half the characteristic period of the oscillator.Comment: Accepted for publication in J. Phys.

Uniject(R) as a delivery system for the once-a-month injectable contraceptive Cyclofem(R) in Brazil

This study assessed the administration of Cyclofem(R) using prefilled Uniject(R) devices. A total of 480 injections were administered divided equally between standard syringes and Uniject. the majority of women (82%) reported that they felt anxious prior to receiving the injection with Uniject. After injection, more than 80% expressed no anxiety about the appearance of uniject or about the technique of injection. A total of 96.3% of the participants reported slight to no pain with Uniject. in comparison to the standard syringe, 5.6% expressed having had more pain with Uniject. Ninety percent of the service providers reported that Uniject was easy to activate and inject and that it was reassuring for users to know that the syringe and needle had never been used previously. Only two service providers demonstrated difficulties in activating the device. No accidental punctures occurred during the manipulation, and incomplete emptying of the Uniject was not observed. in conclusion, Uniject is a good device for the administration of the injectable contraceptive Cyclofem. It is likely to be appropriate for the delivery oi other injectable contraceptives after the necessary stability tests have been performed.UNIV ESTADUAL CAMPINAS,CTR ASSISTENCIA INTEGRAL SAUDE MULHER,DEPT TOCOGINECOL,CAMPINAS,BRAZILCTR ASSISTENCIA INTEGRAL SAUDE MULHER,S BERNARDO CA,SP,BRAZILESCOLA PAULISTA MED,São Paulo,BRAZILMATERN ESCOLA VILA NOVA CACHOERINHA,São Paulo,BRAZILESCOLA PAULISTA MED,São Paulo,BRAZILWeb of Scienc

Molecular dynamics study of methane hydrate formation at a water/methane interface

We present molecular dynamics simulation results of a liquid water/methane interface, with and without an oligomer of poly(methylaminoethylmethacrylate), PMAEMA. PMAEMA is an active component of a commercial low dosage hydrate inhibitor (LDHI). Simulations were performed in the constant NPT ensemble at temperatures of 220, 235, 240, 245, and 250 K and a pressure of 300 bar. The simulations show the onset of methane hydrate growth within 30 ns for temperatures below 245 K in the methane/water systems; at 240 K there is an induction period of ca. 20 ns, but at lower temperatures growth commences immediately. The simulations were analyzed to calculate hydrate content, the propensity for hydrogen bond formation, and how these were affected by both temperature and the presence of the LDHI. As expected, both the hydrogen bond number and hydrate content decreased with increasing temperature, though little difference was observed between the lowest two temperatures considered. In the presence of PMAEMA, the temperature below which sustained hydrate growth occurred was observed to decrease. Some of the implications for the role of PMAEMA in LDHIs are discussed

Uniject As A Delivery System For The Once-a-month Injectable Contraceptive Cyclofem In Brazil.

This study assessed the administration of Cyclofem using prefilled Uniject devices. A total of 480 injections were administered divided equally between standard syringes and Uniject. The majority of women (82%) reported that they felt anxious prior to receiving the injection with Uniject. After injection, more than 80% expressed no anxiety about the appearance of Uniject or about the technique of injection. A total of 96.3% of the participants reported slight to no pain with Uniject. In comparison to the standard syringe, 5.6% expressed having had more pain with Uniject. Ninety percent of the service providers reported that Uniject was easy to activate and inject and that it was reassuring for users to know that the syringe and needle had never been used previously. Only two service providers demonstrated difficulties in activating the device. No accidental punctures occurred during the manipulation, and incomplete emptying of the Uniject was not observed. In conclusion, Uniject is a good device for the administration of the injectable contraceptive Cyclofem. It is likely to be appropriate for the delivery of other injectable contraceptives after the necessary stability tests have been performed.53115-

Self-administration With Uniject Of The Once-a-month Injectable Contraceptive Cyclofem.

The objective of this study was to evaluate women's acceptance of and ability to self-administrate the injectable contraceptive Cyclofem using prefilled UniJect devices. A total of 102 women were invited to participate in the study. Fourteen women (13.7%) refused to participate. Of the remaining 88 women, 32 women (31.4%) consented to participate and were trained using oranges but were still afraid of the procedure and ultimately refused to self-administer the injections. Only 56 women (55%) ultimately self-injected Cyclofem with UniJect. They performed a total of 144 injections, all of them on the ventral side of the thigh. When nurses evaluated women's ability to activate the devices, they found that more than 80% were successful in both the group of women that later self-administered the injections and the group that did not. The evaluation of the self-administered injection technique showed that more than 90% of the women correctly self-administered the contraceptive using UniJect. With respect to the opinion of the women about the self-administration of the contraceptive, more than 50% (32 of 56) of women who self-injected preferred to self-administer the injection and said that they wished to continue with the self-administration, one-third (17) reported that they were afraid, and seven women (12.5%) expressed the opinion that the injection in the thigh was more painful than the administration in the buttocks or arm. In conclusion, our study showed that women can be trained to successfully self-administer the monthly injectable contraceptive Cyclofem and generally respond positively to UniJect.56301-

Self-administration With Uniject® Of The Once-a-month Injectable Contraceptive Cyclofem®

The objective of this study was to evaluate women's acceptance of and ability to self-administrate the injectable contraceptive Cyclofem® using prefilled UniJect® devices. A total of 102 women were invited to participate in the study. Fourteen women (13.7%) refused to participate. Of the remaining 88 women, 32 women (31.4%) consented to participate and were trained using oranges but were still afraid of the procedure and ultimately refused to self-administer the injections. Only 56 women (55%) ultimately self-injected Cyclofem with UniJect. They performed a total of 144 injections, all of them on the ventral side of the thigh. When nurses evaluated women's ability to activate the devices, they found that more than 80% were successful in both the group of women that later self-administered the injections and the group that did not. The evaluation of the self-administered injection technique showed that more than 90% of the women correctly self-administered the contraceptive using UniJect. With respect to the opinion of the women about the self-administration of the contraceptive, more than 50% (32 of 56) of women who self-injected preferred to self-administer the injection and said that they wished to continue with the self-administration, one-third (17) reported that they were afraid, and seven women (12.5%) expressed the opinion that the injection in the thigh was more painful than the administration in the buttocks or arm. In conclusion, our study showed that women can be trained to successfully self-administer the monthly injectable contraceptive Cyclofem and generally respond positively to UniJect.Women's capability to self-administer the monthly injectable contraceptive, Cyclofem, through use of prefilled UniJect devices was evaluated in 88 volunteers recruited from three Brazilian health clinics. After training in self-injection in which oranges were used for practice, only 56 of these women (55%) elected to continue with the study. They performed a total of 144 injections on the ventral side of the thigh. When nurses evaluated women's ability to activate the UniJect device, they found more than 80% of women trained in the method and 93% of those who actually performed self-injection used the technique correctly in an angle of 90 degrees. 32 (57.1%) of the 56 women who self-injected indicated they preferred this method and wished to continue to self-inject at home, another 17 (30.4%) reported they liked the method but were afraid to perform it on their own, and seven (12.5%) complained of pain associated with injection in the thigh compared with the buttocks or arm. Self-administration of injectable contraception, a popular method in Latin American countries, has the potential to increase contraceptive coverage as well as reduce costs associated with transportation to a source of contraception. If women are to perform self-injection at home rather than at a clinic, they will require reminders about the dates of reinjection and the importance of aseptic procedures and proper disposal of injecting equipment.565301304Hirata, Y., System for the treatment of diabetes in Japan (1994) Diabetes Res Clin Pract, 24 (SUPPL.), pp. S229-32Wikland, M., Borg, J., Forsberg, A.S., Jakobsson, A.H., Svalander, P., Waldeenstrom, U., Human chorionic gonadotrophin self-administered by the subcutaneous route to induce oocyte maturation in an in-vitro fertilization and embryo transfer programme (1995) Hum Reprod, 10, pp. 1667-1670Virag, R., Bachir, D., Lee, K., Galacteros, F., Preventive treatment of priapism in sickle cell disease with oral and self-administered intracavernous injection of etilefrine (1996) Urology, 47, pp. 777-781Gheorghiu, S., Godschalk, M., Gentili, A., Mulligan, T., Quality of life in patients using self-administered intracavernous injections of prostaglandin E1, for erectile dysfunction (1996) J Urol, 156, pp. 80-81Newton, J.R., D'Arcangues, C., Hall, P.E., "Once-a-month" combined injectable contraceptives (1994) J Obstet Gynaecol, 14 (SUPPL. 1), pp. S1-S34Benagiano, G., Long-acting systemic contraceptives (1977) Regulation of Human Fertility, pp. 323-360. , Diczfalusy E, ed., Copenhagen: ScriptorBahamondes, L., Marchi, N., Cristofoletti, M.L., Uniject as a delivery system for the once-a-month injectable contraceptive cyclofem in Brazil (1996) Contraception, 53, pp. 115-119Mauldin, W.P., Miller, V.C., Contraceptive use and commodity costs in developing countries, 1994-2005 (1994) Technical Report #18, 18. , New York: United Nations Population Fund(1992) Demographic and Health Survey, 1991, , Profamilia and Macro International Inc(1992) Demographic and Health Survey, 1991/1992, , Macro International Inc(1991) Demographic and Health Survey, 1990, , Profamilia and Macro International IncBruce, J., (1989) Fundamental Elements of the Quality of Care: A Simple Framework, , The Population Council, Working Papers, New York, Ma