Rhombic embeddings of planar graphs with faces of degree 4

Given a finite or infinite planar graph all of whose faces have degree 4, we study embeddings in the plane in which all edges have length 1, that is, in which every face is a rhombus. We give a necessary and sufficient condition for the existence of such an embedding, as well as a description of the set of all such embeddings.Comment: 11 pages, 3 figure

Design and Benchmark Testing for Open Architecture Reconfigurable Mobile Spirometer and Exhaled Breath Monitor with GPS and Data Telemetry.

Portable and wearable medical instruments are poised to play an increasingly important role in health monitoring. Mobile spirometers are available commercially, and are used to monitor patients with advanced lung disease. However, these commercial monitors have a fixed product architecture determined by the manufacturer, and researchers cannot easily experiment with new configurations or add additional novel sensors over time. Spirometry combined with exhaled breath metabolite monitoring has the potential to transform healthcare and improve clinical management strategies. This research provides an updated design and benchmark testing for a flexible, portable, open access architecture to measure lung function, using common Arduino/Android microcontroller technologies. To demonstrate the feasibility and the proof-of-concept of this easily-adaptable platform technology, we had 43 subjects (healthy, and those with lung diseases) perform three spirometry maneuvers using our reconfigurable device and an office-based commercial spirometer. We found that our system compared favorably with the traditional spirometer, with high accuracy and agreement for forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC), and gas measurements were feasible. This provides an adaptable/reconfigurable open access "personalized medicine" platform for researchers and patients, and new chemical sensors and other modular instrumentation can extend the flexibility of the device in the future

Pediatric Emergency Care Capacity in a Low-Resource Setting: An assessment of district hospitals in Rwanda

BACKGROUND: Health system strengthening is crucial to improving infant and child health outcomes in low-resource countries. While the knowledge related to improving newborn and child survival has advanced remarkably over the past few decades, many healthcare systems in such settings remain unable to effectively deliver pediatric advance life support management. With the introduction of the Emergency Triage, Assessment and Treatment plus Admission care (ETAT+)-a locally adapted pediatric advanced life support management program-in Rwandan district hospitals, we undertook this study to assess the extent to which these hospitals are prepared to provide this pediatric advanced life support management. The results of the study will shed light on the resources and support that are currently available to implement ETAT+, which aims to improve care for severely ill infants and children. METHODS: A cross-sectional survey was undertaken in eight district hospitals across Rwanda focusing on the availability of physical and human resources, as well as hospital services organizations to provide emergency triage, assessment and treatment plus admission care for severely ill infants and children. RESULTS: Many of essential resources deemed necessary for the provision of emergency care for severely ill infants and children were readily available (e.g. drugs and laboratory services). However, only 4/8 hospitals had BVM for newborns; while nebulizer and MDI were not available in 2/8 hospitals. Only 3/8 hospitals had F-75 and ReSoMal. Moreover, there was no adequate triage system across any of the hospitals evaluated. Further, guidelines for neonatal resuscitation and management of malaria were available in 5/8 and in 7/8 hospitals, respectively; while those for child resuscitation and management of sepsis, pneumonia, dehydration and severe malnutrition were available in less than half of the hospitals evaluated. CONCLUSIONS: Our assessment provides evidence to inform new strategies to enhance the capacity of Rwandan district hospitals to provide pediatric advanced life support management. Identifying key gaps in the health care system is required in order to facilitate the implementation and scale up of ETAT+ in Rwanda. These findings also highlight a need to establish an outreach/mentoring program, embedded within the ongoing ETAT+ program, to promote cross-hospital learning exchanges

Analytical low-thrust satellite maneuvers for rapid ground target revisit

This paper presents an analytical solution for a low-thrust maneuver to reduce the flyover time of a given terrestrial target. The work extends the general solution previously developed by the authors for a 3-phase spiral transfer that results in a change in the relative right ascension of the ascending node and argument of latitude of satellites in a constellation, by varying the orbital period and the J2 effect experienced by each satellite. This work improves the accuracy of the existing method by including the periodic effects of J2 in the analytical solution. Using these improved equations, a calculation of the flyover time of a given latitude can be determined, and the passes for which the target longitude is in view identified. Validation against a numerical orbit propagator shows the analytical method to accurately predict the sub-satellite point of the satellite to within ±1° of longitude after 15 days. A case study is performed showing that the method can successfully be used to reduce the time of flyover of Los Angeles from 14 days to just 1.97 days, with a change of velocity (ΔV) of 63m/s. The full exploration of the solution space shows the problem to be highly complex, such that an increase in the ΔV used for a maneuver will not necessarily reduce the time of flyover, potentially making optimization using a numerical solution challenging. It also shows that very similar flyover times can be achieved with very different ΔV usage. As such, an overview of the solution space is extremely valuable in allowing an informed trade-off between the time of flyover and maneuver ΔV

Mekanisme pencairan dana pembiayaan mudharabah dengan agunan cash collateral : studi kasus pada KSPPS Arthamadina Banyuputih-Batang

Koperasi simpan pinjam dan pembiayaan syariah merupakan koperasi yang kegiatan usahanya meliputi pinjaman, simpanan, dan pembiayaan yang pengoprasiannya sesuai dengan perinsip syariah dan juga terdapat kegiatan pengelolaan zakat, infaq/sodakoh, dan wakaf. KSPPS Arthamadina dalam menyalurkan danannya menggunakan akad mudharabah atau akad kerja sama antara shohibul maal dan mudharib, kspps arthamadina juga menyediakan pembiayaan dengan agunan cast collateral untuk mempermudah anggota atau calon anggotanya yang akan mengajukan pembiayaan tetapi tidak mempunyai fix asset. Adapun rumusan masalah yang dalam penelitian ini, adalah bagaimana mekanisme pencairan dana pembiayaan dan apa saja yang dijadikan pertimbangan dalam melakukan pembiayaan dengan agunan cast collateral di KSPPS Arthamadina. Penelitian ini menggunakan metode kualitatif, dengan menggunakan pendekatan deskritif dengan berusaha mengambarkan hasil penelitian yang apa adanya. Teknik pengumpulan data dengan observasi, wawancara, dan dokumentasi. KSPPS Arthamadina adalah tempat yang dijadikan penelitian yang daerah kerjanya di Kabupaten Batang, lebih tepatnya di Jl. Lokojoyo Km. 1 Banyuputih, Batang 51271. Dari hasil penelitian KSPPS Arthamadina belum sepenuhnya menggunakan prinsip syariah dikarenakan di KSPPS Arthamadina masih menggunakan persentase dalam bagi hasilnya. Pembiayaan dengan agunan cast collateral juga diterapkan untuk memberikan kemudahan, kesejahteraan, dan membantu anggotanya yang tidak memiliki agunan fix asset tetapi masih dapat melakukan pembiayaan dengan plafon yang kecil

Patterns of Coral Disease across the Hawaiian Archipelago: Relating Disease to Environment

In Hawaii, coral reefs occur across a gradient of biological (host abundance), climatic (sea surface temperature anomalies) and anthropogenic conditions from the human-impacted reefs of the main Hawaiian Islands (MHI) to the pristine reefs of the northwestern Hawaiian Islands (NWHI). Coral disease surveys were conducted at 142 sites from across the Archipelago and disease patterns examined. Twelve diseases were recorded from three coral genera (Porites, Montipora, Acropora) with Porites having the highest prevalence. Porites growth anomalies (PorGAs) were significantly more prevalent within and indicative of reefs in the MHI and Porites trematodiasis (PorTrm) was significantly more prevalent within and indicative of reefs in the NWHI. Porites tissue loss syndrome (PorTLS) was also important in driving regional differences but that relationship was less clear. These results highlight the importance of understanding disease ecology when interpreting patterns of disease occurrence. PorTrm is caused by a parasitic flatworm that utilizes multiple hosts during its life cycle (fish, mollusk and coral). All three hosts must be present for the disease to occur and higher host abundance leads to higher disease prevalence. Thus, a high prevalence of PorTrm on Hawaiian reefs would be an indicator of a healthy coral reef ecosystem. In contrast, the high occurrence of PorGAs within the MHI suggests that PorGAs are related, directly or indirectly, to some environmental co-factor associated with increased human population sizes. Focusing on the three indicator diseases (PorGAs, PorTrm, PorTLS) we used statistical modeling to examine the underlying associations between disease prevalence and 14 different predictor variables (biotic and abiotic). All three diseases showed positive associations with host abundance and negative associations with thermal stress. The association with human population density differed among disease states with PorGAs showing a positive and PorTrm showing a negative association, but no significant explanatory power was offered for PorTLS

Opposite-side flavour tagging of B mesons at the LHCb experiment

The calibration and performance of the oppositeside flavour tagging algorithms used for the measurements of time-dependent asymmetries at the LHCb experiment are described. The algorithms have been developed using simulated events and optimized and calibrated with B + →J/ψK +, B0 →J/ψK ∗0 and B0 →D ∗− μ + νμ decay modes with 0.37 fb−1 of data collected in pp collisions at √ s = 7 TeV during the 2011 physics run. The oppositeside tagging power is determined in the B + → J/ψK + channel to be (2.10 ± 0.08 ± 0.24) %, where the first uncertainty is statistical and the second is systematic

Measurement of the Bs0→J/ψKS0B_s^0\to J/\psi K_S^0 branching fraction

The $B_s^0\to J/\psi K_S^0$ branching fraction is measured in a data sample corresponding to 0.41$fb^{-1}$ of integrated luminosity collected with the LHCb detector at the LHC. This channel is sensitive to the penguin contributions affecting the sin2$\beta$ measurement from $B^0\to J/\psi K_S^0$ The time-integrated branching fraction is measured to be $BF(B_s^0\to J/\psi K_S^0)=(1.83\pm0.28)\times10^{-5}$. This is the most precise measurement to date

Measurement of the CP-violating phase \phi s in Bs->J/\psi\pi+\pi- decays

Measurement of the mixing-induced CP-violating phase phi_s in Bs decays is of prime importance in probing new physics. Here 7421 +/- 105 signal events from the dominantly CP-odd final state J/\psi pi+ pi- are selected in 1/fb of pp collision data collected at sqrt{s} = 7 TeV with the LHCb detector. A time-dependent fit to the data yields a value of phi_s=-0.019^{+0.173+0.004}_{-0.174-0.003} rad, consistent with the Standard Model expectation. No evidence of direct CP violation is found.Comment: 15 pages, 10 figures; minor revisions on May 23, 201

Measurement of the CP-violating phase phi_s in the decay Bs->J/psi phi

We present a measurement of the time-dependent CP-violating asymmetry in B_s -> J/psi phi decays, using data collected with the LHCb detector at the LHC. The decay time distribution of B_s -> J/psi phi is characterized by the decay widths Gamma_H and Gamma_L of the heavy and light mass eigenstates of the B_s-B_s-bar system and by a CP-violating phase phi_s. In a sample of about 8500 B_s -> J/psi phi events isolated from 0.37 fb^-1 of pp collisions at sqrt(s)=7 TeV we measure phi_s = 0.15 +/- 0.18 (stat) +/- 0.06 (syst) rad. We also find an average B_s decay width Gamma_s == (Gamma_L + Gamma_H)/2 = 0.657 +/- 0.009 (stat) +/- 0.008 (syst) ps^-1 and a decay width difference Delta Gamma_s == Gamma_L - Gamma_H} = 0.123 +/- 0.029 (stat) +/- 0.011 (syst) ps^-1. Our measurement is insensitive to the transformation (phi_s,DeltaGamma_s --> pi - phi_s, - Delta Gamma_s.Comment: 9 pages, 3 figure