A general theorem on the divergence of vortex beams

The propagation and divergence properties of beams carrying orbital angular momentum (OAM) play a crucial role in many applications. Here we present a general study on the divergence of optical beams with OAM. We show that the mean absolute value of the OAM imposes a lower bound on the value of the beam divergence. We discuss our results for two different definitions of the divergence, the so called rms or encircled-energy. The bound on the rms divergence can be expressed as a generalized uncertainty principle, with applications in long-range communication, microscopy and 2D quantum systems.Comment: RevTex, published versio

Luteal Blood Flow and progesterone concentration during first and second postpartum estrous cycle in lactating dairy cows

The aim of the present study was to determine the differences in corpus luteum (CL) functionality between the first postpartum estrous cycle and the following cycle in lactating dairy cows. Luteal blood flow (LBF), luteal size and blood progesterone (P4) concentration were monitored during the first and second postpartum estrous cycle. During the first and second postpartum estrous cycle, the mean LBF value increased (p < .05) from early to late dioestrus, while it decreased rapidly in proestrus, resulting statistically lower (p < .05) than those registered in all previous phases. Statistically significant differences were not observed between overall LBF during first and second postpartum estrous cycle (p > .05). During the first postpartum estrous cycle, P4 blood concentrations showed a significant reduction (p < .05) from dioestrus to proestrus. A different trend of P4 concentrations was observed during the second postpartum estrous cycle, where mean P4 value registered in proestrus resulted statistically lower than those registered in the previous cycle phases (p < .05). The mean P4 concentration registered over the first postpartum estrous cycle resulted statistically lower (p < .05) than that registered during the second one. A significant correlation between P4 concentrations and LBF was registered only during the second postpartum estrous cycle. Results indicate that during the first postpartum estrous cycle, P4 concentration was independent of luteal blood flow and luteal size

Peningkatan Aktivitas dan Hasil Pembelajaran IPA Menggunakan Metode Eksperimen pada Sdn 04 Pemahan Ketapang

The purpose of this study is to describes the increase in the activity of student learning through demonstration method in class VI Elementary School 04 pemahan Ketapang. The methods This study uses descriptive method, by means of collecting data in the form of sheets of observations and test results to learn. This form of research is Classroom Action Research ( CAR). Data collection techniques are using direct observation techniques with a data collection tool in the form of observation sheet. Research shows that there is an increase in planning learning objects of heat using an experimental method by 34.25 % , 26.75 % implementation of learning and learning activities in class VI students of SDN 04 Pemahan of 22.22 % , as well as increased activity and student learning outcomes in class VI SDN 04 Pemahan Ketapang District, which is in cycle 1 with students who achieve mastery of grade 3 students learn to 7 students or an increase of 55.55 % . The average value of the first cycle of 66.29 rising to 79.44. Therefore, researchers can say that an increase in student learning outcomes in science subjects using the experimental method in class VI SDN 04 Pemahan Ketapang of 13.15 %

A Methodology for Parameter Estimation of Nonlinear Single Track Models from Multibody Full Vehicle Simulation

In vehicle dynamics, simple and fast vehicle models are required, especially in the framework of real-time simulations and autonomous driving software. Therefore, a trade-off between accuracy and simulation speed must be pursued by selecting the appropriate level of detail and the corresponding simplifying assumptions based on the specific purpose of the simulation. The aim of this study is to develop a methodology for map and parameter estimation from multibody simulation results, to be used for simplified vehicle modelling focused on handling performance. In this paper, maneuvers, algorithms and results of the parameter estimation are reported, together with their integration in single track models with increasing complexity and fidelity. The agreement between the multibody model, used as reference, and four single track models is analyzed and discussed through the evaluation of the correlation index. The good match between the models validates the adopted simulation methodology both during steady-state and during transient maneuvers. In a similar way, this method could be applied to experimental data gathered from a real instrumented car rather than from a multibody model

Effect of platelet lysate on uterine response of mares susceptible to persistent mating-induced endometritis

Many mares are susceptible to persistent mating-induced endometritis (PMIE), an important cause of reduced fertility. Platelet lysate (PL) derives from freeze-thawing platelets after concentration, so that growth factors are released from the platelets. Among the advantages of PL compared to platelet-rich plasma (PRP), it can be frozen stored and allogenic use for PL might also be conceivable. Platelet-rich plasma beneficially reduced inflammatory response in PMIE mares when administered 24 h pre- or 4 h post-AI. The aim of this study was to test the effect of PL on inflammatory uterine response in mares susceptible to PMIE. A total of 14 mares susceptible to PMIE (based on presence of fluid or inflammatory cells 24 h after AI) underwent an untreated (Ctr) cycle followed by a treated (PL) cycle. From each mare, 100 mL of citrated whole blood was obtained for PRP production by centrifugation. The resultant PRP was brought to a final volume of 10 mL with platelet poor plasma and frozen at −80 °C to obtain PL. On untreated cycles, mares were inseminated with frozen-thawed semen 36 h after ovulation induction. On treated cycles, PL was thawed, infused into the uterus 12 h after ovulation induction, and AIs were performed 24 h later. The number of neutrophils in uterine cytology (score 1(normal)-3(severe inflammation)) evaluated by optical microscopy, uterine fluid accumulation (height x width) and uterine edema (score 0–3) observed in ultrasonography, were analysed. Pregnancy was evaluated by ultrasonography 14 days after ovulation. A significant decrease (P < 0.05) was observed on cytology score (PL 1.3 ± 0.1 vs Ctr 2.0 ± 0.1), fluid accumulation (PL 79.5 ± 30.1 mm2 vs Ctr 342.7 ± 52.9 mm2) and edema score (PL 1.8 ± 0.2 vs Ctr 2.3 ± 0.2) in treated mares. Pregnancy rate in PL-treated cycles (3/12) and control cycles (2/14), were not significantly different (P > 0.05). According to the results, we conclude that treatment with PL in mares classified as susceptible to PMIE appears to reduce the inflammatory response after breeding, based on clinical signs of uterine edema, IUF accumulation and PMNs migration

Wells Syndrome with Multiorgan Involvement Mimicking Hypereosinophilic Syndrome

Eosinophil-associated diseases represent a spectrum of heterogeneous disorders, where blood and cutaneous eosinophilia is the most important feature and eosinophils are the principal cause of cutaneous lesions. These diseases show some similarities in the clinical features but also many distinctive characteristics [Saurat et al., Dermatologia e malattie sessualmente trasmesse, Milano, Masson, 2000]. Wells syndrome is one of these disorders and is an uncommon recurrent inflammatory dermatosis, rarely associated to signs and symptoms of multiple organ involvement [Arch Dermatol 2006;142:1157–1161]. Hypereosinophilic syndrome, in contrast, constitutes a group of idiopathic disorders characterized by blood eosinophilia for at least 6 months, associated with single or multiple organ system dysfunction [Arch Dermatol 2006;142:1157–1161]. Clinically atypical Wells syndrome with multiorgan involvement is reported here. A correct diagnosis is difficult in this case, but clinical and histopathological features are compatible with this diagnosis. The reported condition likely represents a borderline hypereosinophilic disease, in which clinical features of both hypereosinophilic syndrome and Wells syndrome are present

Measuring degree-degree association in networks

The Pearson correlation coefficient is commonly used for quantifying the global level of degree-degree association in complex networks. Here, we use a probabilistic representation of the underlying network structure for assessing the applicability of different association measures to heavy-tailed degree distributions. Theoretical arguments together with our numerical study indicate that Pearson's coefficient often depends on the size of networks with equal association structure, impeding a systematic comparison of real-world networks. In contrast, Kendall-Gibbons' $\tau_{b}$ is a considerably more robust measure of the degree-degree association

Menopausal hormone therapy and sleep-disordered breathing: evidence for a healthy user bias

PurposeObservational studies suggest that menopausal hormone therapy protects against sleep-disordered breathing, but such findings may be biased by a "healthy user effect." When the Women's Health Initiative Study reported in 2002 that estrogen-progestin therapy increases heart disease risk, many women discontinued hormone therapy. We investigate healthy user bias in the association of hormone therapy with sleep-disordered breathing in the Sleep in Midlife Women Study.MethodsA total of 228 women aged 38 to 62 years were recruited from the Wisconsin Sleep Cohort Study. They underwent polysomnography to measure apnea-hypopnea index, at home semiannually from 1997 to 2006, and in the sleep laboratory every four years (n = 1828 studies). Hormone therapy was recorded monthly. Linear models with empirical standard errors regressed logarithm of apnea-hypopnea index on hormone use with a pre- or post-July 2002 interaction, adjusting for menopause and age.ResultsThe association of hormone therapy and sleep-disordered breathing was heterogeneous (P < .01); apnea-hypopnea index among users was 15% lower in the early period (95% confidence interval, -27% to -1%), but similar to nonusers in the late.ConclusionsHormone therapy was negatively associated with sleep-disordered breathing only until the Women's Health Initiative results were publicized. Hormone therapy may have been a marker for healthfulness in the early period, creating a spurious association with sleep-disordered breathing