Three Dimensional Visualization and Fractal Analysis of Mosaic Patches in Rat Chimeras: Cell Assortment in Liver, Adrenal Cortex and Cornea

The production of organ parenchyma in a rapid and reproducible manner is critical to normal development. In chimeras produced by the combination of genetically distinguishable tissues, mosaic patterns of cells derived from the combined genotypes can be visualized. These patterns comprise patches of contiguously similar genotypes and are different in different organs but similar in a given organ from individual to individual. Thus, the processes that produce the patterns are regulated and conserved. We have previously established that mosaic patches in multiple tissues are fractal, consistent with an iterative, recursive growth model with simple stereotypical division rules. Fractal dimensions of various tissues are consistent with algorithmic models in which changing a single variable (e.g. daughter cell placement after division) switches the mosaic pattern from islands to stripes of cells. Here we show that the spiral pattern previously observed in mouse cornea can also be visualized in rat chimeras. While it is generally held that the pattern is induced by stem cell division dynamics, there is an unexplained discrepancy in the speed of cellular migration and the emergence of the pattern. We demonstrate in chimeric rat corneas both island and striped patterns exist depending on the age of the animal. The patches that comprise the pattern are fractal, and the fractal dimension changes with the age of the animal and indicates the constraint in patch complexity as the spiral pattern emerges. The spiral patterns are consistent with a loxodrome. Such data are likely to be relevant to growth and cell division in organ systems and will help in understanding how organ parenchyma are generated and maintained from multipotent stem cell populations located in specific topographical locations within the organ. Ultimately, understanding algorithmic growth is likely to be essential in achieving organ regeneration in vivo or in vitro from stem cell populations

Sex difference and intra-operative tidal volume: Insights from the LAS VEGAS study

BACKGROUND: One key element of lung-protective ventilation is the use of a low tidal volume (VT). A sex difference in use of low tidal volume ventilation (LTVV) has been described in critically ill ICU patients.OBJECTIVES: The aim of this study was to determine whether a sex difference in use of LTVV also exists in operating room patients, and if present what factors drive this difference.DESIGN, PATIENTS AND SETTING: This is a posthoc analysis of LAS VEGAS, a 1-week worldwide observational study in adults requiring intra-operative ventilation during general anaesthesia for surgery in 146 hospitals in 29 countries.MAIN OUTCOME MEASURES: Women and men were compared with respect to use of LTVV, defined as VT of 8 ml kg-1 or less predicted bodyweight (PBW). A VT was deemed 'default' if the set VT was a round number. A mediation analysis assessed which factors may explain the sex difference in use of LTVV during intra-operative ventilation.RESULTS: This analysis includes 9864 patients, of whom 5425 (55%) were women. A default VT was often set, both in women and men; mode VT was 500 ml. Median [IQR] VT was higher in women than in men (8.6 [7.7 to 9.6] vs. 7.6 [6.8 to 8.4] ml kg-1 PBW, P < 0.001). Compared with men, women were twice as likely not to receive LTVV [68.8 vs. 36.0%; relative risk ratio 2.1 (95% CI 1.9 to 2.1), P < 0.001]. In the mediation analysis, patients' height and actual body weight (ABW) explained 81 and 18% of the sex difference in use of LTVV, respectively; it was not explained by the use of a default VT.CONCLUSION: In this worldwide cohort of patients receiving intra-operative ventilation during general anaesthesia for surgery, women received a higher VT than men during intra-operative ventilation. The risk for a female not to receive LTVV during surgery was double that of males. Height and ABW were the two mediators of the sex difference in use of LTVV.TRIAL REGISTRATION: The study was registered at Clinicaltrials.gov, NCT01601223

Epidemiology, practice of ventilation and outcome for patients at increased risk of postoperative pulmonary complications: LAS VEGAS - An observational study in 29 countries

BACKGROUND Limited information exists about the epidemiology and outcome of surgical patients at increased risk of postoperative pulmonary complications (PPCs), and how intraoperative ventilation was managed in these patients. OBJECTIVES To determine the incidence of surgical patients at increased risk of PPCs, and to compare the intraoperative ventilation management and postoperative outcomes with patients at low risk of PPCs. DESIGN This was a prospective international 1-week observational study using the ‘Assess Respiratory Risk in Surgical Patients in Catalonia risk score’ (ARISCAT score) for PPC for risk stratification. PATIENTS AND SETTING Adult patients requiring intraoperative ventilation during general anaesthesia for surgery in 146 hospitals across 29 countries. MAIN OUTCOME MEASURES The primary outcome was the incidence of patients at increased risk of PPCs based on the ARISCAT score. Secondary outcomes included intraoperative ventilatory management and clinical outcomes. RESULTS A total of 9864 patients fulfilled the inclusion criteria. The incidence of patients at increased risk was 28.4%. The most frequently chosen tidal volume (V T) size was 500 ml, or 7 to 9 ml kg−1 predicted body weight, slightly lower in patients at increased risk of PPCs. Levels of positive end-expiratory pressure (PEEP) were slightly higher in patients at increased risk of PPCs, with 14.3% receiving more than 5 cmH2O PEEP compared with 7.6% in patients at low risk of PPCs (P ˂ 0.001). Patients with a predicted preoperative increased risk of PPCs developed PPCs more frequently: 19 versus 7%, relative risk (RR) 3.16 (95% confidence interval 2.76 to 3.61), P ˂ 0.001) and had longer hospital stays. The only ventilatory factor associated with the occurrence of PPCs was the peak pressure. CONCLUSION The incidence of patients with a predicted increased risk of PPCs is high. A large proportion of patients receive high V T and low PEEP levels. PPCs occur frequently in patients at increased risk, with worse clinical outcome.</p

Geoeconomic variations in epidemiology, ventilation management, and outcomes in invasively ventilated intensive care unit patients without acute respiratory distress syndrome: a pooled analysis of four observational studies

Background: Geoeconomic variations in epidemiology, the practice of ventilation, and outcome in invasively ventilated intensive care unit (ICU) patients without acute respiratory distress syndrome (ARDS) remain unexplored. In this analysis we aim to address these gaps using individual patient data of four large observational studies. Methods: In this pooled analysis we harmonised individual patient data from the ERICC, LUNG SAFE, PRoVENT, and PRoVENT-iMiC prospective observational studies, which were conducted from June, 2011, to December, 2018, in 534 ICUs in 54 countries. We used the 2016 World Bank classification to define two geoeconomic regions: middle-income countries (MICs) and high-income countries (HICs). ARDS was defined according to the Berlin criteria. Descriptive statistics were used to compare patients in MICs versus HICs. The primary outcome was the use of low tidal volume ventilation (LTVV) for the first 3 days of mechanical ventilation. Secondary outcomes were key ventilation parameters (tidal volume size, positive end-expiratory pressure, fraction of inspired oxygen, peak pressure, plateau pressure, driving pressure, and respiratory rate), patient characteristics, the risk for and actual development of acute respiratory distress syndrome after the first day of ventilation, duration of ventilation, ICU length of stay, and ICU mortality. Findings: Of the 7608 patients included in the original studies, this analysis included 3852 patients without ARDS, of whom 2345 were from MICs and 1507 were from HICs. Patients in MICs were younger, shorter and with a slightly lower body-mass index, more often had diabetes and active cancer, but less often chronic obstructive pulmonary disease and heart failure than patients from HICs. Sequential organ failure assessment scores were similar in MICs and HICs. Use of LTVV in MICs and HICs was comparable (42\ub74% vs 44\ub72%; absolute difference \u20131\ub769 [\u20139\ub758 to 6\ub711] p=0\ub767; data available in 3174 [82%] of 3852 patients). The median applied positive end expiratory pressure was lower in MICs than in HICs (5 [IQR 5\u20138] vs 6 [5\u20138] cm H2O; p=0\ub70011). ICU mortality was higher in MICs than in HICs (30\ub75% vs 19\ub79%; p=0\ub70004; adjusted effect 16\ub741% [95% CI 9\ub752\u201323\ub752]; p&lt;0\ub70001) and was inversely associated with gross domestic product (adjusted odds ratio for a US$10 000 increase per capita 0\ub780 [95% CI 0\ub775\u20130\ub786]; p&lt;0\ub70001). Interpretation: Despite similar disease severity and ventilation management, ICU mortality in patients without ARDS is higher in MICs than in HICs, with a strong association with country-level economic status. Funding: No funding

Providing Services to Migrant Farmworkers: Special Supplemental Food Program for Women, Infants and Children, and the Commodity Supplemental Food Program

Excerpts from the report Introduction: The first handbook on providing services to migrant farmworkers was distributed by the Food and Nutrition Service (FNS) in 1979. Since that time, significant progress has been made in the delivery of migrant services. FNS recognizes, however, the need for additional technical assistance in order to continue to improve the accessibility of the Special Supplemental Food Program for Women, Infants, and Children (WIC) and the Commodity Supplemental Food Program (CSFP) to migrant populations. Therefore, this updated handbook brings together all pertinent program information and compiles it into a single resource document. The handbook is intended to serve as a comprehensive guide for State and local agencies administering WIC and CSF programs in areas where migrant farmworkers are employed. In addition, legislation which authorizes the WIC program, Public Law 95-627, requires USDA to report to the National Advisory Council on Maternal, Infant, and Fetal Nutrition on efforts to ensure, to the maximum extent possible, that WIC services are provided to members of eligible migrant populations as such persons move among States. Therefore, this handbook also serves as such a report. The WIC and CSF programs are part of the complex of public programs serving migrants. It is the intent of the WIC and CSF programs to provide needy migrant families with some protection against inadequate nutrition as well as to provide access to health care. The continuation of WIC or CSF program benefits to this population as it migrates during the year is an important step towards improving the health status of many at-risk pregnant women and their children -- now and in the years to come. Such benefits can only be acknowledged if significant efforts are made to provide program benefits to needy migrants regardless of where they live and work

Power Measurement of Performance Bicycles (Semester Unknown) IPRO 324

Competitive cyclists around the world are using technology to monitor training data in order to improve their training methods. Power measurements are important to such training, however existing power meters are expensive and the cyclist must replace existing crank sets. Thus, IPRO 324 intends to develop a power meter that not only can be applied to any crank set but that will accurately collect and transmit data to current cycling computers as well as cost significantly less than comparable systems.Deliverable

Power Measurement of Performance Bicycles (Semester Unknown) IPRO 324: PowerMeasurementsForPerformanceBikesIPRO324FinalReportSp11_redacted

Competitive cyclists around the world are using technology to monitor training data in order to improve their training methods. Power measurements are important to such training, however existing power meters are expensive and the cyclist must replace existing crank sets. Thus, IPRO 324 intends to develop a power meter that not only can be applied to any crank set but that will accurately collect and transmit data to current cycling computers as well as cost significantly less than comparable systems.Deliverable

An electrical-level superposed-edge approach to statistical serial link simulation

rute-force simulation approaches to estimating serial-link bit-error rates (BERs) become computationally intractable for the case when BERs are low and the interconnect electrical response is slow enough to generate intersymbol interference that spans dozens of bit periods. Electrical-level statistical simulation approaches based on superposing pulse responses were developed to address this problem, but such pulse-based methods have difficulty analyzing jitter and rise/fall asymmetry. In this paper we present a superposing-edge approach for statistical simulation, as edge-based methods handle rise/fall asymmetry and jitter in straightforward way. We also resolve a key problem in using edge-based approaches, that edges are always correlated, by deriving an efficient inductive approach for propagating the edge correlations. Examples are presented demonstrating the edge-based method's accuracy and effectiveness in analyzing combinations of uniform, Gaussian, and periodic distributed random jitter

Power Measurement of Performance Bicycles (Semester Unknown) IPRO 324: PowerMeasurementsForPerformanceBikesIPRO324EthicsSp11

Competitive cyclists around the world are using technology to monitor training data in order to improve their training methods. Power measurements are important to such training, however existing power meters are expensive and the cyclist must replace existing crank sets. Thus, IPRO 324 intends to develop a power meter that not only can be applied to any crank set but that will accurately collect and transmit data to current cycling computers as well as cost significantly less than comparable systems.Deliverable