S-matrix poles and the second virial coefficient

For cutoff potentials, a condition which is not a limitation for the calculation of physical systems, the S-matrix is meromorphic. We can express it in terms of its poles, and then calculate the quantum mechanical second virial coefficient of a neutral gas. Here, we take another look at this approach, and discuss the feasibility, attraction and problems of the method. Among concerns are the rate of convergence of the 'pole' expansion and the physical significance of the 'higher' poles.Comment: 20 pages, 8 tables, submitted to J. Mol. Phy

Locating Planetesimal Belts in the Multiple-planet Systems HD 128311, HD 202206, HD 82943, and HR 8799

In addition to the Sun, six other stars are known to harbor multiple planets and debris disks: HD 69830, HD 38529, HD 128311, HD 202206, HD 82943, and HR 8799. In this paper, we set constraints on the location of the dust-producing planetesimals around the latter four systems. We use a radiative transfer model to analyze the spectral energy distributions of the dust disks (including two new Spitzer IRS spectra presented in this paper), and a dynamical model to assess the long-term stability of the planetesimals' orbits. As members of a small group of stars that show evidence of harboring a multiple planets and planetesimals, their study can help us learn about the diversity of planetary systems

Modeling the video distribution link in the Next Generation Optical Access Networks

In this work we present a model for the design and optimization of the video distribution link in the next generation optical access network. We analyze the video distribution performance in a SCM-WDM link, including the noise, the distortion and the fiber optic nonlinearities. Additionally, we consider in the model the effect of distributed Raman amplification, used to extent the capacity and the reach of the optical link. In the model, we use the nonlinear Schrödinger equation with the purpose to obtain capacity limitations and design constrains of the next generation optical access networks. In this work we present a model for the design and optimization of the video distribution link in the next generation optical access network. We analyze the video distribution performance in a SCM-WDM link, including the noise, the distortion and the fiber optic nonlinearities. Additionally, we consider in the model the effect of distributed Raman amplification, used to extent the capacity and the reach of the optical link. In the model, we use the nonlinear Schrödinger equation with the purpose to obtain capacity limitations and design constrains of the next generation optical access networks

Human schistosomiasis

Human schistosomiasis-or bilharzia-is a parasitic disease caused by trematode fl ukes of the genus Schistosoma. By conservative estimates, at least 230 million people worldwide are infected with Schistosoma spp. Adult schistosome worms colonise human blood vessels for years, successfully evading the immune system while excreting hundreds to thousands of eggs daily, which must either leave the body in excreta or become trapped in nearby tissues. Trapped eggs induce a distinct immune-mediated granulomatous response that causes local and systemic pathological eff ects ranging from anaemia, growth stunting, impaired cognition, and decreased physical fi tness, to organ-specifi c eff ects such as severe hepatosplenism, periportal fi brosis with portal hypertension, and urogenital infl ammation and scarring. At present, preventive public health measures in endemic regions consist of treatment once every 1 or 2 years with the isoquinolinone drug, praziquantel, to suppress morbidity. In some locations, elimination of transmission is now the goal; however, more sensitive diagnostics are needed in both the fi eld and clinics, and integrated environmental and health-care management will be needed to ensure elimination. © Chataway et al. Open Access article distributed under the terms of CC BY

OXPHOS Inhibition via LUC7L2 as a Target for SF3B1-Mutant Myelodysplastic Syndrome

SF3B1 gene mutations are the most common spliceosome mutations seen in myelodysplastic syndrome (MDS) patients. Though it is well known SF3B1 mutations cause downstream changes in erythroid differentiation and the cell cycle, which leads to malignancy, metabolic changes arising from this mutation are unknown. We conducted RNA sequencing from SF3B1-mutant MDS patient samples and found several genes related to metabolism were alternatively spliced. Of these, LUC7L2 was selected as our target as previous studies show its involvement in promoting oxidative phosphorylation (OXPHOS) via various downstream mechanisms when knocked down.We show that OXPHOS is increased in MOLM-13 myeloid malignant cells when LUC7L2 is inhibited. The results suggested that this gene, which is alternatively spliced and shows lower expression in SF3B1-mutant MDS, increases myeloid malignant dependence on OXPHOS

Schistosomiasis-associated pulmonary arterial hypertension: a systematic review.

Schistosomiasis-associated pulmonary arterial hypertension (Sch-PAH) is a life-threatening complication of chronic hepatosplenic schistosomiasis. It is suggested to be the leading cause of pulmonary arterial hypertension (PAH) worldwide. However, pathophysiological data on Sch-PAH are scarce. We examined the hypothesis that there are pronounced similarities in pathophysiology, haemodynamics, and survival of Sch-PAH and idiopathic PAH (iPAH).This systematic review and meta-analysis was registered in the PROSPERO database (identifier CRD42018104066). A systematic search and review of the literature was performed according to PRISMA guidelines for studies published between 01 January 1990 and 29 June 2018.For Sch-PAH, 18 studies evaluating pathophysiological mechanisms, eight studies on haemodynamics (n=277), and three studies on survival (n=191) were identified. 16 clinical registries reporting data on haemodynamics and survival including a total of 5792 patients with iPAH were included for comparison. Proinflammatory molecular pathways are involved in both Sch-PAH and iPAH. The transforming growth factor (TGF)-β signalling pathway is upregulated in Sch-PAH and iPAH. While there was no difference in mean pulmonary artery pressure (54±17 mmHg versus 55±15 mmHg, p=0.29), cardiac output (4.4±1.3 L·min-1 versus 4.1±1.4 L·min-1, p=0.046), and cardiac index (2.6±0.7 L·min-1·m-2 versus 2.3±0.8 L·min-1·m-2, p<0.001) were significantly higher in Sch-PAH compared to iPAH, resulting in a lower pulmonary vascular resistance in Sch-PAH (10±6 Woods units versus 13±7 Woods units, p<0.001). 1- and 3-year survival were significantly better in the Sch-PAH group (p<0.001).Sch-PAH and iPAH share common pathophysiological mechanisms related to inflammation and the TGF-β signalling pathway. Patients with Sch-PAH show a significantly better haemodynamic profile and survival than patients with iPAH

Multi-Triplet Magnons in SrCu2_2(BO3_3)2_2 Studied by Thermal Conductivity Measurements in Magnetic Fields

We have measured the thermal conductivity parallel to the a-axis of the Zn-free and 1% Zn-substituted SrCu$_{2-x}$Zn$_x$(BO$_3$)$_2$ in magnetic fields up to 14 T, in order to examine the thermal conductivity due to the multi-triplet magnons. It has been found that the thermal conductivity peak observed in the spin gap state is suppressed by the substitution of Zn for Cu in high magnetic fields above 6 T, while it is not changed in low magnetic fields below 6 T. The results suggest that the thermal conductivity peak in the spin-gap state of SrCu$_2$(BO$_3$)$_2$ is composed of not only thermal conductivity due to phonons but also that due to the multi-triplet magnons in high fields above 6 T.Comment: 7 pages, 2 figure

Advancing Vaccine Equity through Community-Based Organizations: Partnering for Vaccine Equity Program Annual Evaluation ReportYear One

The Centers for Disease Control and Prevention (CDC) launched the Partnering for Vaccine Equity (P4VE) program in 2020 to address racial and ethnic disparities in adult immunization rates, particularly for COVID-19 and influenza. In 2021, P4VE directed $156 million to over 500 national, state, and community-based organizations (CBOs) to improve equitable access to vaccination in communities by promoting vaccine confidence and addressing barriers to vaccination opportunities.The Urban Institute is partnering with CDC to support a subset of CBOs participating in the P4VE program. In the first year of the P4VE initiative (April 30, 2021, to April 29, 2022), the Urban Institute provided grant subawards and tailored program support and technical assistance to 29 CBOs. This report presents findings from an evaluation of CBOs' performance on P4VE program objectives in the first year, including challenges and successes CBOs experienced in their efforts to improve vaccine equity