Study on the Kinetic Anti-Missile Fragment Based on NASA Model

2012 ◽  
Vol 271-272 ◽  
pp. 584-588 ◽  
Author(s):  
Wei Jie Wang ◽  
Huai Rong Shen ◽  
Yi Yong Li

The question of the anti-missile fragment produced by the Kinetic Kill Vehicle (KKV) intercepting the Tactical Ballistic Missile (TBM) is studied. It turns out the anti-missile fragment are composite outcome of the impact and explosion. By analysis the National Aeronautics and Space Administration (NASA) impact breakup model is suggested to calculate the fragment charac-teristic. The minimum mass threshold of effective fragment is deduced; the damages probability model that the debris cloud impacts the cooperative target is established based on Poisson distribu-tion. The simulation case indicates that the damage probability can achieve the 10-3 magnitude, and should attach importance to this threat.

Diabetologia ◽  
2021 ◽  
Author(s):  
David Z. I. Cherney ◽  
◽  
Bernard Charbonnel ◽  
Francesco Cosentino ◽  
Samuel Dagogo-Jack ◽  
...  

Abstract Aims/hypothesis In previous work, we reported the HR for the risk (95% CI) of the secondary kidney composite endpoint (time to first event of doubling of serum creatinine from baseline, renal dialysis/transplant or renal death) with ertugliflozin compared with placebo as 0.81 (0.63, 1.04). The effect of ertugliflozin on exploratory kidney-related outcomes was evaluated using data from the eValuation of ERTugliflozin effIcacy and Safety CardioVascular outcomes (VERTIS CV) trial (NCT01986881). Methods Individuals with type 2 diabetes mellitus and established atherosclerotic CVD were randomised to receive ertugliflozin 5 mg or 15 mg (observations from both doses were pooled), or matching placebo, added on to existing treatment. The kidney composite outcome in VERTIS CV (reported previously) was time to first event of doubling of serum creatinine from baseline, renal dialysis/transplant or renal death. The pre-specified exploratory composite outcome replaced doubling of serum creatinine with sustained 40% decrease from baseline in eGFR. In addition, the impact of ertugliflozin on urinary albumin/creatinine ratio (UACR) and eGFR over time was assessed. Results A total of 8246 individuals were randomised and followed for a mean of 3.5 years. The exploratory kidney composite outcome of sustained 40% reduction from baseline in eGFR, chronic kidney dialysis/transplant or renal death occurred at a lower event rate (events per 1000 person-years) in the ertugliflozin group than with the placebo group (6.0 vs 9.0); the HR (95% CI) was 0.66 (0.50, 0.88). At 60 months, in the ertugliflozin group, placebo-corrected changes from baseline (95% CIs) in UACR and eGFR were −16.2% (−23.9, −7.6) and 2.6 ml min−1 [1.73 m]−2 (1.5, 3.6), respectively. Ertugliflozin was associated with a consistent decrease in UACR and attenuation of eGFR decline across subgroups, with a suggested larger effect observed in the macroalbuminuria and Kidney Disease: Improving Global Outcomes in Chronic Kidney Disease (KDIGO CKD) high/very high-risk subgroups. Conclusions/interpretation Among individuals with type 2 diabetes and atherosclerotic CVD, ertugliflozin reduced the risk for the pre-specified exploratory composite renal endpoint and was associated with preservation of eGFR and reduced UACR. Trial registration ClinicalTrials.gov NCT01986881 Graphical abstract


2021 ◽  
pp. 088307382110001
Author(s):  
Jody L. Lin ◽  
Joseph Rigdon ◽  
Keith Van Haren ◽  
MyMy Buu ◽  
Olga Saynina ◽  
...  

Background: Gastrostomy tube (G-tube) placement for children with neurologic impairment with dysphagia has been suggested for pneumonia prevention. However, prior studies demonstrated an association between G-tube placement and increased risk of pneumonia. We evaluate the association between timing of G-tube placement and death or severe pneumonia in children with neurologic impairment. Methods: We included all children enrolled in California Children’s Services between July 1, 2009, and June 30, 2014, with neurologic impairment and 1 pneumonia hospitalization. Prior to analysis, children with new G-tubes and those without were 1:2 propensity score matched on sociodemographics, medical complexity, and severity of index hospitalization. We used a time-varying Cox proportional hazard model for subsequent death or composite outcome of death or severe pneumonia to compare those with new G-tubes vs those without, adjusting for covariates described above. Results: A total of 2490 children met eligibility criteria, of whom 219 (9%) died and 789 (32%) had severe pneumonia. Compared to children without G-tubes, children with new G-tubes had decreased risk of death (hazard ratio [HR] 0.47, 95% confidence interval [CI] 0.39-0.55) but increased risk of the composite outcome (HR 1.21, CI 1.14-1.27). Sensitivity analyses using varied time criteria for definitions of G-tube and outcome found that more recent G-tube placement had greater associated risk reduction for death but increased risk of severe pneumonia. Conclusion: Recent G-tube placement is associated with reduced risk of death but increased risk of severe pneumonia. Decisions to place G-tubes for pulmonary indications in children with neurologic impairment should weigh the impact of severe pneumonia on quality of life.


2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Yun Xue ◽  
Zhiwen Liu ◽  
Jie Luo ◽  
Zhihao Ma ◽  
Meizhen Zhang ◽  
...  

The prediction of stock market’s trend has become a challenging task for a long time, which is affected by a variety of deterministic and stochastic factors. In this paper, a biclustering algorithm is introduced to find the local patterns in the quantized historical data. The local patterns obtained are regarded as the trading rules. Then the trading rules are applied in the short term prediction of the stock price, combined with the minimum-error-rate classification of the Bayes decision theory under the assumption of multivariate normal probability model. In addition, this paper also makes use of the idea of the stream mining to weaken the impact of historical data on the model and update the trading rules dynamically. The experiment is implemented on real datasets and the results prove the effectiveness of the proposed algorithm.


Author(s):  
Xingyun Jia ◽  
Liguo Wang ◽  
Qun Zheng ◽  
Hai Zhang ◽  
Yuting Jiang

Performance of generic rim seal configurations, axial-clearance rim seal (ACS), radial-clearance rim seal (RCS), radial-axial clearance rim seal (RACS) are compared under realistic working conditions. Conjugate heat transfer analysis on rim seal is performed in this paper to understand the impact of ingestion on disc temperature. Results show that seal effectiveness and cooling effectiveness of RACS are the best when compared with ACS and RCS, the minimum mass flow rate for seal of RACS is 75% of that of RCS, and 34.6% of ACS. Authors compare the disc temperature distribution between different generic rim seal configurations where the RACS seems to be favorable in terms of low disc temperature. In addition, RACS has higher air-cooled aerodynamic efficiency, minimizing the mainstream performance penalty when compared with ACS and RCS. Corresponding to the respective minimum mass flow rate for seal, the air-cooled aerodynamic efficiency of RACS is 23.71% higher than that of ACS, and 12.79% higher than the RCS.


2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Afonso Santos ◽  
Eunice Cacheira ◽  
Sílvia Coelho ◽  
Paulo Telles Freitas

Abstract Background and Aims Preeclampsia is potentially serious complication of pregnacy and frequently requires admission in ICU. Management of this condition involves treatment with magnesium sulfate to prevent progression to eclampsia or even more adverse outcomes such as maternal or fetal death. However the exact dose of magnesium needed is still to be determined and few studies have analyzed the impact of this therapheutic intervention in women admitted in intensive care units, in terms of outcomes and adverse effects. Herein, we present a series of patients diagnosed with preeclampsia, including its most severe presentations with eclampsia or HELLP syndrome, admitted in an intensive care unit. Method Demographic, clinical and laboratorial data of women admitted between January-2016 and December-2018 to the Polyvalent Intensive Care Unit (ICU) of Hospital Fernando Fonseca, a tertiary Hospital in Portugal, with the diagnosis of preeclampsia, were retrospectively collected. Diagnosis of preeclampsia, HELLP syndrome and eclampsia were performed according to the ISSHP criteria (2004). Acute Kidney Injury (AKI) was defined according to the KDIGO criteria. The study was approved by the Ethical Committee of the institution. Results 42 patients were included, 52.3% (n=22) diagnosed as non-severe preeclampsia; 31% (n=13) as HELLP syndrome and 16.7% (n=7) as eclampsia. Mean age at presentation was 29.6±6.6 years old, with 52,4% (n=22) caucasian and 47.6% (n=20) black. Most patients were admitted in ICU in post-partum period, after cesarian delivery in 95.2% (n=40). Seven patients (16.7%) had a previous diagnosis of hypertension; 11.9% (n=5) were obese; none has previous chronic kidney disease. At presentation, most patients diagnosed with preeclampsia had three diagnostic criteria (28.6%, n=12), including hypertension. Renal dysfunction was found in 80.9% (n=34) of patients, with proteinuria >200mg/dL in 69% (n=29) and AKI in 19% (n=8). Mean Hb of 11.1±2.1g/dL, with median platelet count of 126000/uL (IQR 72000-201500) and median LDH of 388mg/dL (IQR 240-773). Pre-partum magnesium sulfate treatment was initiated in 78.6% (n=33) of patients, but only 2.4% (n=1) had previous magnesemia levels determination. During the stay in ICU, daily levels of seric magnesium levels were obtained, with the highest median values found at day one after admission. Adverse events related to hypermagnesemia (bradipnea) occurred in 50% (n=21) of patients. In six patients (14.3%), treatment was stopped because of high levels of magnesemia or adverse events. 14.3% (n=6) progressed to eclampsia and fetal death occured also in 14.3% (n=6). Maternal deaths did not occur. By logistic binary regression we found out that weight was an independent risk factor for the development of the composite outcome of eclampsia or fetal death, when adjusted to age, race, AKI, hemoglobin, platelet count, ALT, LDH, serum albumin and proteinuria. (p=0.04). However, when Magnesium was included in the analysis, all variables lost significance. An association between SOFA and SAPS scores and the occurrence of the composite outcome has been found (p= 0.03 and p=0.019, respectively). Conclusion Most patients with preeclampsia received treatment with magnesium sulfate without previous measurement of serum levels. Bradipnea occurred in 50% of cases and treatment had to be stooped in almost 15%. Nevertheless, magnesium levels were not independently associated with the composite outcome of fetal death or eclampsia. Future studies should evaluate if a dose adjusted to a specific target of magnesium seric level could be associated with less adverse effects while still reducing the risk associated with preeclampsia.


Author(s):  
J. Zhao ◽  
F. Tan ◽  
C. Liu ◽  
C. Sun

The near-earth space environment is cluttered with man-made debris and naturally occurring meteoroids, which is a big menace to the safety of satellites and spacecrafts. This paper is addressed on the failure response of aluminum shields under hypervelocity impact of milligrame level flyer. A compacted electric gun is employed to accelerate a mylar flyer up to 10 km/s. Failure response of Ly12 aluminum shields with different thickness and layers impacted by mylar flyer with different velocities is under investigation. The spallation is observed in the rear free surface of 4 mm thick monolithic aluminum shield, and its fracture mechanism changes from plastic to brittle when loading pressure is above 13 GPa. A perforation with a diameter 8 mm in the impacted area of the 4mm thick Ly12 shield is observed after which is impacted by 0.1 mm thick mylar flyer 8mm in diameter with velocity 8.2 km/s. When three layers of shields are impacted, the debris clouds (DC) are observed in the first and the second spaces respectively during the impact process by high speed camera, and its leftover can be observed on the surface of the third plate. The shape of the first debris cloud head is a little flat, and its speed of lateral expansion is very slow, which is different from those impacted by spherical projectile, and its formation mechanics mainly attributes to multi-spallations based on the analysis of simulation.


2020 ◽  
Vol 45 (3) ◽  
pp. 431-441
Author(s):  
Precil Diego Miranda de Menezes Neves ◽  
Rafaela Bezerra Brito Pinheiro ◽  
Cristiane Bitencourt Dias ◽  
Luis Yu ◽  
Leonardo de Abreu Testagrossa ◽  
...  

Background and Aim: Immunoglobulin A nephropathy (IgAN) is the most common primary glomerulopathy. The Oxford classification was recently updated to include crescents as markers of poor prognosis. The aim of this study was to evaluate the impact of cellular crescents on the prognosis of patients with IgAN in Brazil. Methods: This was a single-centre retrospective analysis of medical records and renal biopsies in patients with IgAN. The renal biopsy findings were classified according to the revised Oxford classification: mesangial hypercellularity, endocapillary hypercellularity (E), segmental glomerulosclerosis (S), tubular atrophy or interstitial fibrosis (T), and crescent formation (C). We evaluated a composite outcome (progression to end-stage renal disease or creatinine doubling). We performed analyses between the patients with crescents in the renal biopsy specimen (C1/C2 group) and those without such crescents (C0 group). Results: We evaluated 111 patients, of whom 72 (65.0%) were women, 80 (72.0%) self-identified as White, 73 (65.6%) were hypertensive, and 95 (85.6%) had haematuria. The distribution of patients according to cellular crescentic lesions was: C0, 80 (72%); C1, 27 (24.4%); C2, 4 (3.6%). The composite outcome was observed in 33 (29.72%) of the 111 patients. In comparison with the C0 group, the C1/C2 group had higher proportions of patients with hypertension (p = 0.04), haematuria (p = 0.03), worse serum creatinine (p = 0.0007), and worse estimated glomerular filtration rate (p = 0.0007). The C1/C2 group also had higher proportions of patients in whom the biopsy specimen was classified as E1 (p = 0.009), S1 (p = 0.001), or T1/T2 (p = 0.03), In addition, the mean follow-up period was shorter in the C1/C2 group (p < 0.0001). Furthermore, the composite outcome was observed in a greater proportion of patients and in a shorter length of time in the C1/C2 group than in the C0 group (p = 0.002 and p = 0.0014, respectively). In a Cox regression analysis, the independent risk factors for the composite outcome had Oxford classifications of S1, T1/T2, and C1/C2. Conclusion: Oxford classification findings of S1, T1/T2, or C1/C2 were independent risk factors for the composite outcome, corroborating previous studies.


2019 ◽  
Vol 13 (3) ◽  
pp. 533-545 ◽  
Author(s):  
Christopher Rini ◽  
Bruce C. Roberts ◽  
Didier Morel ◽  
Rick Klug ◽  
Benjamin Selvage ◽  
...  

Background: Limited published data exists quantifying the influence of human factors (HF) and pen needle (PN) design on delivery outcomes of pen injection systems. This preclinical in vivo study examines the impact of PN hub design and applied force against the skin during injection on needle penetration depth (NPD). Method: To precisely locate injection depth, PN injections (20 µl; 2 IU, U-100 volume equivalent) of iodinated contrast agent were administered to the flank of Yorkshire swine across a range of clinically relevant application forces against the skin (0.25, 0.75, 1.25, and 2.0 lbf). The NPD, representing in vivo needle tip depth in SC tissue, from four 32 G × 4 mm PN devices (BD Nano™ 2nd Gen and three commercial posted-hub PN devices; n = 75/device/force, 1200 total) was measured by fluoroscopic imaging of the resulting depot. Results: The reengineered hub design more closely achieved the 4 mm target NPD with significantly less variability ( P = .006) than commercial posted-hub PN devices across the range of applied injection forces. Calculations of IM (intramuscular) injection risk completed through in silico probability model, using NPD and average human tissue thickness measurements, displayed a commensurate reduction (~2-8x) compared to conventional PN hub designs. Conclusions: Quantifiable differences in injection depth were observed between identical labeled length PN devices indicating that hub design features, coupled with aspects of variable injection technique, may influence injection depth accuracy and consistency. The reengineered hub design may reduce the impact of unintended individual technique differences by improving target injection depth consistency and reducing IM injection potential.


2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S842-S842
Author(s):  
Daniel Friedman ◽  
Karen Zurek ◽  
Leyla Asadi ◽  
Mao-Cheng Lee ◽  
Holly Hoang

Abstract Background Clostridioides difficile infection (CDI) is an important cause of morbidity and mortality and management continues to evolve. For laboratories that diagnose by detection of toxin gene, it is unclear whether reporting toxin production is additive to patient care. Furthermore, is there still a role for metronidazole (MNZ) given treatment guidelines now recommend vancomycin (VAN) as first-line therapy for non-severe cases? We analyzed cases of CDI in our hospital to assess outcomes of patients on MNZ vs. VAN and with or without toxin production. Methods A retrospective chart review of inpatients with CDI (based on detection of C. difficile toxin gene by PCR) was conducted between November 2017 and August 2018. Comparison of demographics and outcomes was performed in a) cases that were toxin-positive by enzyme immunoassay vs. negative and b) non-severe cases initially managed with MNZ vs. VAN. Results 76 patients were included (46 toxin-positive, 30 toxin-negative). Toxin-positive patients were older (mean age 77 vs. 62, p = 0.002) but had similar disease severity and initial treatment. A CDI recurrence occurred in 22% vs 0% in the toxin-positive cases (p = 0.006). Any CDI-related complication occurred in 23% of toxin-negative and 35% of toxin-positive cases (ns). After adjusting for toxin-status, age, and severity, the odds ratio of the composite outcome of any complication with toxin-positive CDI was not significant (OR 1.45 95% CI 0.45 -4.6, p = 0.52). There were 37 (49%) patients with non-severe CDI (27 MNZ, 10 VAN). Patients treated with VAN had higher stooling/day (6.3 vs 4.4, p = 0.04) and heart rate (p = 0.02). Initial MNZ use was associated with treatment escalation in 48% of cases compared with 10% in those treated with VAN alone (p = 0.03). CDI-associated mortality was higher in the VAN group (2/10 vs 0/27, p = 0.017). The rate of other complications was not significantly different. Conclusion Although no difference in the composite outcome of any CDI-related complication was detected between toxin positive vs negative patients, toxin-positivity may predict patients at risk for subsequent recurrence. Patients with non-severe CDI did not have increased risk of complications when managed with MNZ; however, they were more likely to require treatment escalation. Disclosures All authors: No reported disclosures.


2011 ◽  
Vol 90-93 ◽  
pp. 805-812 ◽  
Author(s):  
Zheng Wei Ye ◽  
Yi Qiang Xiang

Based on the method of separation of wind speed and direction variable, considering the wind direction frequency function, ascending order to calculate the probability of the actual distribution of the sample, extreme type Ⅰ (Gumbel) and three parameters of extreme type Ⅱ (Frechet) and extreme type Ⅲ (Weibull) probability distribution to fit the sample, this paper has analyzed the weather station observations of 34 consecutive years of the joint distribution of wind speed and direction near to a huge bridge, gained the basic design wind speed in different directions, comparatively analyzed the impact of the sampling interval of change on the basic wind speed as well. The results shows: wind speed in different directions at the same location or different sampling intervals samples of the wind speed sample may be subject to different types of extreme value distribution, should separately fitting; different wind direction frequency of extreme wind speed occurrence and the basic wind speed there are certain differences, taking into account the joint distribution of wind speed and direction is necessary to determine the design basic wind speed of the bridge, and will be conservative without considering the joint distribution; for the same sample wind speed matrix, the shorter the sampling intervals, the optimal distribution of the higher probability model fitting precision, the smaller the basic wind speed, the more economic and reasonable the results.


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