403 research outputs found

    Heterogeneous condensation of the Lennard-Jones vapor onto a nanoscale seed particle

    Full text link
    The heterogeneous condensation of a Lennard-Jones vapor onto a nanoscale seed particle is studied using molecular dynamics simulations. Measuring the nucleation rate and the height of the free energy barrier using the mean first passage time method shows that the presence of a weakly interacting seed has little effect on the work of forming very small cluster embryos but accelerates the rate by lowering the barrier for larger clusters. We suggest that this results from a competition between the energetic and entropic features of cluster formation in the bulk and at the heterogeneity. As the interaction is increased, the free energy of formation is reduced for all cluster sizes. We also develop a simple phenomenological model of film formation on a small seed that captures the general features of the nucleation process for small heterogeneities. A comparison of our simulation results with the model shows that heterogeneous classical nucleation theory provides a good estimate of the critical size of the film but significantly over-estimates the size of the barrier.Comment: 9 pages, 10 figures, In Print J. Chem. Phy

    Perencanaan Pembangunan Sumber Daya Aparatur melalui Penyusunan Formasi Pegawai Negeri Sipil Daerah di Kabupaten Magetan

    Full text link
    Pelaksanaan pembangunan dan penyelenggaraan pelayanan sektor publik yang efektif dan efisien membutuhkan sumber daya aparatur pemerintah yang profesional, memiliki kompetensi dan jumlah yang tepat, namun hal tersebut belum sepenuhnya terwujud. Untuk itu diperlukan perbaikan dalam pengelolaan kepegawaian ke arah yang lebih baik terutama perencanaan untuk formasi pegawai. Penelitian ini bertujuan untuk mendeskripsikan: (1) Perencanaan sumber daya aparatur melalui penyusunan formasi Pegawai Negeri Sipil Daerah yang dilaksanakan di Kabupaten Magetan; dan (2) Faktor-faktor yang berkaitan dengan penyusunan formasi Pegawai Negeri Sipil Daerah di Kabupaten Magetan. Dalam penelitian ini menggunakan pendekatan kualitatif, dengan jenis deskriptif. Hasil penelitian menunjukkan bahwa: (1) Perencanaan sumber daya aparatur di Kabupaten Magetan dituangkan dalam Rencana Strategis Badan Kepegawaian Daerah Kabupaten Magetan yang diwujudkan dalam berbagai perencanaan di bidang aparatur antara lain penyusunan formasi Pegawai Negeri Sipil yang pada tahun 2013 menggunakan data analisis jabatan dan analisis beban kerja, namun hasilnya tidak optimal karena data tersebut tidak akurat/valid; (2) faktor-faktor yang berkaitan dan menyebabkan hal tersebut adalah komitmen manajemen, kebijakan pemerintah, sumber daya perencana kepegawaian, sistem informasi sumber daya manusia atau SIMPEG dan anggaran yang belum sesuai dengan yang diharapkan

    Rearing system effects on live weight gain of large white turkeys

    Get PDF
    The aim of this study was to determine the effect of three production systems on live weight gain (LWG) of white turkeys by repeated measures analysis of variance (ANOVA) and profile analysis. A total of 81 turkey poults were assigned to intensive (7 male and 19 female), semi-intensive (9 male and 19 female) and extensive groups (11 male and 16 female) at one day old. The poults were wing-banded at day 1 after hatching and weighed individually each week through 16 weeks old. The birds were managed similarly through eight weeks old. After that time, the intensive group was fed concentrated feed indoors. The birds of the semi-intensive group had access to pasture for eight hours a day, and received 50% of the concentrated feed that was consumed by the intensive group. The birds in the extensive group were kept outdoors with shade and grazed on pasture, but did not receive concentrated feed. The bi-weekly LWG of the extensive, intensive and semi-intensive groups were 1191.4 g, 990.6 g and 872.1 g, respectively. Through the 16 weeks of the trial, the effects on LWG of production system, age, and interaction of age and production system were highly significant (P <0.01) in the repeated measures ANOVA. The profile analysis also showed highly significant (P <0.01) production system effects and interaction of production system and age on LWG. Scheffe’s test indicated that the intensive, semi-intensive, and extensive treatments differed (P <0.05)

    Impact of extended sinus surgery on allograft infection, allograft function and overall survival in cystic fibrosis lung transplant recipients

    Full text link
    BACKGROUND Studies investigating the impact of sinus surgery for cystic fibrosis (CF) patients performed early after lung transplantation (Ltx) are scarce. Recent studies evaluating frequency of respiratory infections and graft outcomes are not available. OBJECTIVES/HYPOTHESIS To determine whether there is a difference in allograft infection, allograft function and overall survival among CF lung transplant recipients with and without concomitant sinus surgery. STUDY DESIGN Retrospective single-center study. METHODS We examined 71 CF patients who underwent Ltx between 2009 and 2019 at our center. Fifty-nine patients had sinus surgery before or/and after transplantation and twelve did not undergo sinus surgery. We assessed the survival, the diagnosis of chronic allograft dysfunction (CLAD) and all elevated (> 5 mg/l) c-reactive protein episodes during the observed period. The infectious events of the upper and lower airways were categorized in mild infections (5-15 mg/l CRP) and severe infections (> 15 mg/l CRP). RESULTS There was no difference in the long-time overall survival (p = 0.87) and no benefit in the short-term survival at 4 year post-transplant (p = 0.29) in both groups. There was no difference in both groups concerning CLAD diagnosis (p = 0.92). The incidence of severe upper and lower airway infections (CRP > 15 mg/l) was significantly decreased in the sinus surgery group (p = 0.015), whereas in mild infections there was a trend to decreased infections in the sinus surgery group (p = 0.056). CONCLUSIONS CF patients undergoing Ltx benefit from extended endoscopic sinus surgery (eESS) in terms of frequency of severe infectious events of the upper and lower airways. There was no difference in overall survival and frequency of CLAD in the two groups

    Pattern and Outcome of Chest Injuries at Bugando Medical Centre in Northwestern Tanzania.

    Get PDF
    Chest injuries constitute a continuing challenge to the trauma or general surgeon practicing in developing countries. This study was conducted to outline the etiological spectrum, injury patterns and short term outcome of these injuries in our setting. This was a prospective study involving chest injury patients admitted to Bugando Medical Centre over a six-month period from November 2009 to April 2010 inclusive. A total of 150 chest injury patients were studied. Males outnumbered females by a ratio of 3.8:1. Their ages ranged from 1 to 80 years (mean = 32.17 years). The majority of patients (72.7%) sustained blunt injuries. Road traffic crush was the most common cause of injuries affecting 50.7% of patients. Chest wall wounds, hemothorax and rib fractures were the most common type of injuries accounting for 30.0%, 21.3% and 20.7% respectively. Associated injuries were noted in 56.0% of patients and head/neck (33.3%) and musculoskeletal regions (26.7%) were commonly affected. The majority of patients (55.3%) were treated successfully with non-operative approach. Underwater seal drainage was performed in 39 patients (19.3%). One patient (0.7%) underwent thoracotomy due to hemopericardium. Thirty nine patients (26.0%) had complications of which wound sepsis (14.7%) and complications of long bone fractures (12.0%) were the most common complications. The mean LOS was 13.17 days and mortality rate was 3.3%. Using multivariate logistic regression analysis, associated injuries, the type of injury, trauma scores (ISS, RTS and PTS) were found to be significant predictors of the LOS (P < 0.001), whereas mortality was significantly associated with pre-morbid illness, associated injuries, trauma scores (ISS, RTS and PTS), the need for ICU admission and the presence of complications (P < 0.001). Chest injuries resulting from RTCs remain a major public health problem in this part of Tanzania. Urgent preventive measures targeting at reducing the occurrence of RTCs is necessary to reduce the incidence of chest injuries in this region

    Normal gas exchange after 30-h ischemia and treatment with phosphodiesterase inhibitor PDI747

    Get PDF
    Objective: Phosphodiesterases (PDEs) negatively regulate the concentrations of cAMP and/or cGMP, which act as downstream second messengers to the prostaglandins. PDE type-4 (PDE4) is selective for cAMP and is found in high concentrations in endothelial, epithelial, and different blood cells. The aim of this study was to evaluate if PDI747, a novel selective inhibitor of PDE4, can restore pretransplant cAMP levels and thereby posttransplant organ function after prolonged cold ischemia. Methods: Left lung transplantation was performed in pigs (25-31 kg). Donor lungs were flushed with low potassium dextran glucose (LPDG) solution only (control, n=5)or, in addition with 1 μmol of PDI747 (PDI747, n=5) and stored for 30 h at 1 °C. PDI747 animals further received a bolus of PDI747 (0.3 mg/kg) 15 min prior to reperfusion and a continuous infusion (0.3 mg/kg per hour) during the 5 h after reperfusion. After occlusion of the right pulmonary arteries and the right main bronchus, hemodynamic and gas exchange parameters and extravascular lung water (EVLW) levels of the transplanted lung were assessed. Results: Two control animals died of severe lung edema leading to heart failure (control, n=3). One animal in the treatment group was excluded due to a patent ductus arteriosus (PDI747, n=4). Gas exchange at the end of the experiment was restored to normal levels in the PDI747 group (Pa, o2 47.6±11.2 kPa, Pa,co2 6.4±1.8 kPa) but not in the control group (Pa, o2 7.7±2.9 kPa, Pa, co2 11.9±3.0 kPa, PPao2<0.0001, PPa, co2=0.06). Extravascular lung water (EVLW) was normal in the PDI747 group (8.5±1.1 ml/kg) and clearly elevated in the control group (16.2±5.6 ml/kg, P=0.007). Airway pressure in the PDI747 group was significantly lower than in the control group (7.8±0.5 cm H2O vs. 11.3±0.6 cm H2O, respectively, P<0.0001). The free radical mediated tissue injury measured by lipid peroxidation (TBARS) was significantly reduced (P=0.001) in the PDI747 group. Conclusions: With the inhibition of PDE4 with PDI747 we achieved normal gas exchange, no posttransplant lung edema, normal airway pressures, and a reduced free radical injury after 30 h of cold ischemi

    Airway complications after lung transplantation: risk factors, prevention and outcome

    Get PDF
    PURPOSE: Anastomotic complications following lung transplantation (LuTx) have been described in up to 15% of patients. Challenging to treat, they are associated with high morbidity and a mortality rate of 2-5%. The aim of this study was to analyze the incidence of complications in a consecutive series of bronchial anastomosis after LuTx at our center and to delineate the potential risk factors. METHODS: Between 1992 and 2007, 441 bronchial anastomoses were performed in 235 patients. Indications for transplantation were cystic fibrosis (35.7%) emphysema (28.1%) pulmonary fibrosis (12.8%) and pulmonary hypertension (7.7%). There were 206 sequential bilateral and 28 single transplants including lobar engraftments in 20 cases. The donor bronchus was shortened to the plane of the lobar carina including the medial wall of the intermediate bronchus. Peribronchial tissue was left untouched. Anastomosis was carried out using a continuous absorbable running suture (PDS 4/0) at the membranous and interrupted sutures at the cartilaginous part. Six elective surveillance bronchoscopies were done monthly during the first half-year post-LuTx, with detailed assessment of the pre- and post-anastomotic airways. RESULTS: One-year survival since 2000 was 90.5%. In all 441 anastomoses performed, no significant dehiscence was observed. In one patient, a small fistula was detected and closed surgically on postoperative day five. Fungal membranes were found in 50% of the anastomoses at 1 month and in 14% at 6 months. Discrete narrowing of the anastomotic lumen without need for intervention was found in 4.9% of patients at 1 month and in 2.4% at 6 months. Age, cytomegalovirus status, induction therapy, immunosuppressive regimen, ischemic time, and ventilation time had no influence on bronchial healing. CONCLUSIONS: Clinically relevant bronchial anastomotic complications after LuTx can be avoided by use of a simple standardized surgical technique. Aggressive antibiotic and antifungal therapy might play an important supportive rol

    Respiratory syncytial virus-associated mortality among young infants in Karachi, Pakistan: A prospective postmortem surveillance study

    Get PDF
    Background: Respiratory syncytial virus (RSV) is an important cause of infant morbidity and mortality and a potential target for maternal immunization strategies. However, data on the role of RSV in young infant deaths in developing countries are limited.Methods: We conducted a community-based mortality surveillance from August 2018-March 2020 for infants ≤6 months in Karachi, Pakistan. We tested (reverse transcription-polymerase chain reaction) nasopharyngeal swabs from deceased infants for presence of RSV. We performed verbal autopsies and calculated odds of RSV-associated mortality with 95% CIs and used multivariable logistic regression to evaluate associations.Results: We collected 490 nasopharyngeal specimens from 1280 eligible infant deaths. There were 377/490 (76.9%) live births and 14/377 (3.7%; 95% CI: 1.8-5.6) were RSV positive. Most deaths occurred in neonates (254/377; 67.4%), males (226/377; 59.9%), and respiratory illnesses (206/377; 54.6%). Postneonatal age (10/14, 71.4%; OR: 5.5; 95% CI: 1.7-18.0), respiratory symptoms (12/14, 85.7%; OR: 5.2; 1.2-23.7), and high RSV season (9/14, 64.3%; OR: 4.4; 1.4-13.3) were associated with RSV mortality. In multivariable logistic regression analysis, respiratory symptoms (OR: 6.6; 95% CI: 1.3-32.5), RSV seasonality (6.1; 1.8-20.4), and age (9.2; 2.6-33.1) were significant predictors of RSV-associated mortality.Conclusions: RSV has a significant mortality burden in early infancy in Karachi, Pakistan. Age, RSV seasonality, and respiratory symptoms were significant predictors of RSV-associated mortality. Our findings have implications for clinical management of young infants with cold-like symptoms, policy development, and research regarding maternal immunization against RSV during pregnancy, in resource-constrained, low-income, and vaccine-hesitant populations

    Portable Microfluidic Integrated Plasmonic Platform for Pathogen Detection

    Get PDF
    Timely detection of infectious agents is critical in early diagnosis and treatment of infectious diseases. Conventional pathogen detection methods, such as enzyme linked immunosorbent assay (ELISA), culturing or polymerase chain reaction (PCR) require long assay times, and complex and expensive instruments, which are not adaptable to point-of-care (POC) needs at resource-constrained as well as primary care settings. Therefore, there is an unmet need to develop simple, rapid, and accurate methods for detection of pathogens at the POC. Here, we present a portable, multiplex, inexpensive microfluidic-integrated surface plasmon resonance (SPR) platform that detects and quantifies bacteria, i.e., Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) rapidly. The platform presented reliable capture and detection of E. coli at concentrations ranging from ∼105 to 3.2 × 107 CFUs/mL in phosphate buffered saline (PBS) and peritoneal dialysis (PD) fluid. The multiplexing and specificity capability of the platform was also tested with S. aureus samples. The presented platform technology could potentially be applicable to capture and detect other pathogens at the POC and primary care settings. © 2015, Nature Publishing Group. All rights reserved

    Right-invariant Sobolev metrics of fractional order on the diffeomorphism group of the circle

    Full text link
    In this paper, we study the geodesic flow of a right-invariant metric induced by a general Fourier multiplier on the diffeomorphism group of the circle and on some of its homogeneous spaces. This study covers in particular right-invariant metrics induced by Sobolev norms of fractional order. We show that, under a certain condition on the symbol of the inertia operator (which is satisfied for the fractional Sobolev norm HsH^{s} for s1/2s \ge 1/2), the corresponding initial value problem is well-posed in the smooth category and that the Riemannian exponential map is a smooth local diffeomorphism. Paradigmatic examples of our general setting cover, besides all traditional Euler equations induced by a local inertia operator, the Constantin-Lax-Majda equation, and the Euler-Weil-Petersson equation.Comment: 40 pages. Corrected typos and improved redactio
    corecore