Rotational States of Magnetic Molecules

We study a magnetic molecule that exhibits spin tunneling and is free to rotate about its anisotropy axis. Exact low-energy eigenstates of the molecule that are superpositions of spin and rotational states are obtained. We show that parameter $\alpha = 2(\hbar S)^2/(I\Delta)$ determines the ground state of the molecule. Here $\hbar S$ is the spin, $I$ is the moment of inertia, and $\Delta$ is the tunnel splitting. The magnetic moment of the molecule is zero at $\alpha \alpha_c$. At $\alpha \to \infty$ the spin of the molecule localizes in one of the directions along the anisotropy axis.Comment: 4 pages, 3 figure

Electron transport through single Mn12 molecular magnets

We report transport measurements through a single-molecule magnet, the Mn12 derivative [Mn12O12(O2C-C6H4-SAc)16(H2O)4], in a single-molecule transistor geometry. Thiol groups connect the molecule to gold electrodes that are fabricated by electromigration. Striking observations are regions of complete current suppression and excitations of negative differential conductance on the energy scale of the anisotropy barrier of the molecule. Transport calculations, taking into account the high-spin ground state and magnetic excitations of the molecule, reveal a blocking mechanism of the current involving non-degenerate spin multiplets.Comment: Accepted for Phys. Rev. Lett., 5 pages, 4 figure

What information is available to women regarding coronavirus and childbirth in Italy? A mixed-methods exploration of the web during the COVID-19 lockdown

Problem: The world is fighting against the COVID-19 pandemic and an infodemic; Italy is one of the most severely affected countries. Background: The internet represents a popular source of health information. In Italy, its use amongst pregnant women and new mothers has increased during the lockdown. No research has examined the nationally accessible information related to childbirth in these unprecedented circumstances. Aim: To explore online information accessible to Italian users concerning childbirth and coronavirus-related issues. Methods: A mixed methods exploration of the web was conducted involving searches on Google, peer discussion forums and midwifery association webpages. Data were analysed both quantitatively and qualitatively. A cross-consultation analysis of themes was performed to identify macro categories of information. Findings: A total of 720 results from free searches, 635 interventions from 97 forums and 68 posts from four midwifery association webpages were analysed. Informative/divulging sources were the most prevalent in Google; pregnancy-related topics appeared more in discussion forums and midwifery association webpages. ‘Prevention’; ‘risks and outcomes’; ‘users’ experiences’ and ‘reorganisation of maternity services’ represent the cross-consultation categories of information. Discussion: Google emerges as the main contributor to the infodemic; national systems of alert and ranking of web sources are needed. Women’s pragmatic needs are more likely to be addressed by peer-discussion forums and midwifery association webpages during and after COVID-19. Conclusion: This is the first study to investigate childbirth-related web information during COVID-19 in Italy; findings may impact on education, research and practice

No evidence of association between prothrombotic gene polymorphisms and the development of acute myocardial infarction at a young age

Background : we investigated the association between 9 polymorphisms of genes encoding hemostasis factors and myocardial infarction in a large sample of young patients chosen because they have less coronary atherosclerosis than older patients, and thus their disease is more likely to be related to a genetic predisposition to a prothrombotic state Methods and Results : this nationwide case-control study involved 1210 patients who had survived a first myocardial infarction at an age of 45 years who underwent coronary arteriography in 125 coronary care units and 1210 healthy subjects matched for age, sex, and geographical origin. None of the 9 polymorphisms of genes encoding proteins involved in coagulation (G-455A -fibrinogen: OR, 1.0; CI, 0.8 to 1.2; G1691A factor V: OR, 1.1; CI, 0.6 to 2.1; G20210A factor II: OR, 1.0; CI, 0.5 to 1.9; and G10976A factor VII: OR, 1.0; CI, 0.8 to 1.3), platelet function (C807T glycoprotein Ia: OR, 1.1; CI, 0.9 to 1.3; and C1565T glycoprotein IIIa: OR, 0.9; CI, 0.8 to 1.2), fibrinolysis (G185T factor XIII: OR, 1.2; CI, 0.9 to 1.6; and 4G/5G plasminogen activator inhibitor type 1: OR, 0.9; CI, 0.7 to 1.2), or homocysteine metabolism (C677T methylenetetrahydrofolate reductase: OR, 0.9; CI, 0.8 to 1.1) were associated with an increased or decreased risk of myocardial infarction Conclusions : this study provides no evidence supporting an association between 9 polymorphisms of genes encoding proteins involved in hemostasis and the occurrence of premature myocardial infarction or protection against it

Exploring the mother's perception of latching difficulty in the first days after birth : an interview study in an Italian hospital

OBJECTIVES: to explore Italian mothers' perception of latching difficulty in the first days postpartum. Latching difficulty is the only qualitative item included in the Breastfeeding Assessment Score (BAS) that has proven to be a valid instrument to identify women at risk of early breast-feeding cessation. DESIGN AND SETTING: a phenomenologic-hermeneutic study was conducted at the Mangiagalli Clinic, Milan, Italy. PARTICIPANTS: fifteen women who received a BAS <8 (indicating an early breast-feeding cessation risk) were interviewed before discharge, and later by phone, for member checking. FINDINGS: six main themes emerged from the interviews: (1) Breast feeding can be difficult due to both the mother and newborn, and encountered problems are mainly physical. (2) Women have developed different strategies to overcome latching difficulties. (3) Early breast feeding, even if difficult, is mostly related to positive feelings. (4) Breast-feeding sustains the child-mother relationship. (5) Mothers have already developed constructive theories about human colostrum, breast milk and artificial milk. (6) Receiving integrated health-care support and education is fundamental to overcome early breast-feeding problems. CONCLUSIONS: the interviews suggest that although mothers experience difficulties during early breast feeding, positive feelings seem to prevail over the negative ones, and mothers have already developed strategies to overcome their latching problems. Receiving support is fundamental, but this must be consistent among health-care professionals. IMPLICATIONS FOR PRACTICE: when evaluating the BAS item 'latching difficulty', midwives should consider that difficulties are primarily related to physical problems. Furthermore, to sustain lactation, mothers should be helped to elicit their experience of early breast feeding, as it can be extremely satisfying, even when difficulties in latching the babies occur

Latching difficulty during breastfeeding: What do Italian mothers say, about their experience? A qualitative study

Introduction Many professional organizations recommend breastfeeding for the first 6 months due to the numerous benefits it has for mother and child. The mother\u2019s breastfeeding experiences in the early postpartum period, are crucial in deciding to continue it. It is important to identify, in the first days after childbirth, women who send messages that are likely to early stop breastfeeding. Many women have said to have breastfeeding difficulties in the first days after birth. Several studies1-4 have explored the motivation of early breastfeeding cessation but little is known on what "breastfeeding difficulty" really means for women. Aim of the study Our goal was to gain a more in-depth understanding of Italian women\u2019s experiences of breastfeeding difficulties, in the early post natal period. Methods The women who received a Breastfeeding Assessment Score5 (BAS) less than 8, and reported \u201clatching difficulties\u201d, were invited to participate in the study. With purposive sampling we recruited 15 women, 48-72 hours after childbirth. We conducted semi-structured interviews which were tape-recorded and verbatim transcribed. The transcripts were read and analyzed using the Grounded Theory method. Results "Latching difficulty" is related to issues including both mother\u2019s and infant\u2019s difficulties. Nipple-pain and infant\u2019s sleepiness were the most reported difficulties. In spite of these difficulties, the sensation related to breastfeeding was \u201chappiness\u201d when the baby sucked the breast, but concern and anxiety were common too. The women reported more impediment in overcoming the breastfeeding difficulty when there was an idealization of breastfeeding, during pregnancy. Conclusion This study enriches the theoretical framework in understanding the dynamics that can contribute to early failure of breastfeeding in Italy. Practical relevance Understanding the meaning of the item \u201clatching difficulty\u201d consents to a more correct interpretation of the BAS5 by the Italian midwives and allows a more accurate identification of the mothers who need support and education during breastfeeding Research implications Since this is a qualitative study, more research is needed to understand the \u201clatching difficulty\u201d in the Italian environment and in other culture

Influence of mechanical hemolysis of blood on two D-dimer immunoassays.

Although there is broad information about the influence of spurious hemolysis on several laboratory tests, less is known on the bias produced on D-dimer testing. Four different pools were obtained from primary blood tubes, and each of them was divided into four aliquots. The first nonhemolyzed was centrifuged, the plasma was separated and then tested for hemolysis index and D-dimer. The second (hemolyzed aliquot A), third (hemolyzed aliquot B) and fourth (hemolyzed aliquot C) aliquots were mechanically hemolyzed by aspirating whole blood one, two and three times through a fine needle. The plasma was then separated and tested for hemolysis index and D-dimer. D-dimer was quantified by HemosIL AcuStar D-dimer and HemosIL D-dimer HS for ACL TOP. Undetectable hemolysis was present in aliquot nonhemolyzed (<0.5 g/l), whereas the concentration of cell-free hemoglobin significantly increased from hemolyzed aliquot A (5.5-7.0 g/l hemoglobin) to hemolyzed aliquot B (11.5 and 15.0 g/l hemoglobin) and hemolyzed aliquot C (20-22 g/l hemoglobin). The plasma concentration of D-dimer decreased from aliquots nonhemolyzed to hemolyzed aliquot C, achieving clinical significance fromhemolyzed aliquot A and hemolyzed aliquot B when measured with D-dimer HS for ACL TOP and AcuStar D-dimer, respectively. The decrease with AcuStar D-dimer was -5 \ub1 3% in hemolyzed aliquot A, -7 \ub1 3% in hemolyzed aliquot B, and -9 \ub1 3% in hemolyzed aliquot C, whereas the decrease with D-dimer HS for ACL TOP was -5 \ub1 3% in hemolyzed aliquot A, -8 \ub1 3% in hemolyzed aliquot B and -9 \ub1 3% in hemolyzed aliquot C. The similar trend towards decreasing values observed when measuring D-dimer with chemiluminescent and turbidimetric immmunoassays on four heterogeneous plasma pools suggest that the hemolysis interference is more likely to be biological than analytical. The modest bias observed in samples with frank hemolysis (i.e. cell-free hemoglobin of 11.5 g/l) confirms that both methods are robust against this type of interference, so that test results might be released in the majority of mildly hemolyzed samples

Sample collection and platelet function testing: influence of vacuum or aspiration principle on PFA-100 test results.

As for other tests of hemostasis, the investigation of platelet function is highly vulnerable to a broad series of preanalytical variables, which span from patient preparation to the final analysis of the specimen and issuance of test results. In particular, there remains much controversy about the influence of manual or vacuum aspiration of blood into primary collection tubes on platelet function testing. Accordingly, we investigated this for the PFA-100. In 12 healthy volunteers, a sample labeled as 'BD-V' was drawn into a 2.7\u200aml BD Vacutainer tube, whereas two additional samples were collected from the opposite arm into 5.0\u200aml Sarstedt S-Monovette tubes by vacuum (SD-V) or manual aspiration (SD-A). All sample were tested on PFA-100 with collagen and ADP (CADP) or collagen and epinephrine (CEPI). The values of both CEPI and CADP obtained in SD-A samples were significantly lower than those obtained in SD-V and BD-V tubes, whereas those of the two evacuated tubes did not significantly differ. On average, CEPI values were prolonged by 11% in SD-V and 13% in BD-V, whereas those of CADP were prolonged by 14% in SD-V and 10% in BD-V, respectively. These findings suggests that the lower shear stress generated by the manual aspiration of blood into the primary collection tube would prevent spurious hyper-activation of platelets, thus, preserving the integrity of their function for subsequent testing on PFA-100. This study underscores the need to define or validate local reference ranges for the PFA-100 based on the collection tube used. Different reference ranges of both CEPI and CADP may also be advisable when venous blood samples are collected with manual aspiration or vacuum principle