The Real Effects of Relational Contracts

Does the “soft side” of management matter? Many managers assert that “firm culture” is strongly correlated with productivity, but there are few robust tests of this assertion. In a set of field experiments, we study driver productivity within a large US logistics company that is arguably transitioning from one relational contract to another, while leaving formal practices and incentives unchanged. We find that sites under the new contract are associated with 1/8 percent higher productivity. Our findings suggest that relational contracts have a first-order effect on productivity and that they can be altered over time.

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Information Used in Detecting Upcoming Collision

Perception ◽

10.1068/p3433 ◽

2003 ◽

Vol 32 (5) ◽

pp. 525-544 ◽

Cited By ~ 20

Author(s):

Reinoud J Bootsma ◽

Cathy M Craig

Keyword(s):

Significant Role ◽

First Order ◽

Near Future ◽

Over Time

In four experiments we examined the nature of the information used in judging whether events would or would not give rise to a collision in the near future. Observers were tested in situations depicting approaches between two objects (lateral approaches) and approaches between an object and the point of observation (head-on approaches), with objects moving according to constant deceleration or sinusoidal deceleration patterns. Judgments were found to be based, to a large extent, on the (in)sufficiency of current deceleration to avoid upcoming collision, as specified optically by tau-dot (τ̇). However, the information specified by tau (τ), that is the current (first-order) time remaining until contact, was also found to play a significant role. We deduce that judgment of upcoming collision is based on the detection of τ and its evolution over time, suggesting that observers are sensitive to Δτ rather than to τ̇ itself.

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International Real Estate Review

International Real Estate Review ◽

10.53383/100223 ◽

2016 ◽

Vol 19 (3) ◽

pp. 265-296

Author(s):

Richard D. Evans ◽

◽

Glenn R. Mueller ◽

Keyword(s):

Markov Chain ◽

Real Estate ◽

Cash Flow ◽

Discounted Cash Flow ◽

First Order ◽

Order Markov Chain ◽

Office Markets ◽

Speed Up ◽

Staying Time ◽

Over Time

Metro market real estate cycles for office, industrial, retail, apartment, and hotel properties may be specified as first order Markov chains, which allow analysts to use a well-developed application, ¡§staying time¡¨. Anticipations for time spent at each cycle point are consistent with the perception of analysts that these cycle changes speed up, slow down, and pause over time. We find that these five different property types in U.S. markets appear to have different first order Markov chain specifications, with different staying time characteristics. Each of the five property types have their longest mean staying time at the troughs of recessions. Moreover, industrial and office markets have much longer mean staying times in very poor trough conditions. Most of the shortest mean staying times are in hyper supply and recession phases, with the range across property types being narrow in these cycle points. Analysts and investors should be able to use this research to better estimate future occupancy and rent estimates in their discounted cash flow (DCF) models.

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Growth analysis of sweet pepper cultivated in coconut fiber in a greenhouse

Horticultura Brasileira ◽

10.1590/s0102-05362011000300010 ◽

2011 ◽

Vol 29 (3) ◽

pp. 316-323 ◽

Cited By ~ 6

Author(s):

Hamilton César de O Charlo ◽

Sueyde F de Oliveira ◽

Renata Castoldi ◽

Pablo F Vargas ◽

Leila T Braz ◽

...

Keyword(s):

Growth Analysis ◽

Dry Mass ◽

Sweet Pepper ◽

Absolute Rate ◽

Coconut Fiber ◽

First Order ◽

Growth Production ◽

Four Blocks ◽

Over Time

Knowledge about the growth of crops allows the planning of rational cultivation methods which contribute to achieve greater potential of plant species, besides supplying information for the construction of descriptive mathematical models of growth. The growth curve of sweet pepper (Eppo hybrid), cultivated in coconut fiber in a greenhouse with fertirrigation, was determined. The experiment consisted initially of 160 plants divided into four blocks. Two plants were analyzed per block every 21 days after transplanting, ending at 189 days after transplant. The cultivation was carried out in plastics pots of 13 L containing coconut fiber, which were arranged in double rows, spaced 0.5 x 0.8 m between simple rows and 1.1 m between double rows. In each harvest the plant growth, production and quality of mature fruits were evaluated. The dry mass of the shoot increased with time, following the experimental model exponential of first order, reaching a maximum of 451.5 g/plant, 189 days after transplanting (DAT). The production of dry mass of leaves, stem, root and fruit also increased over time reaching maximum values of 68.7, 65.8, 11.5 and 302.9 g/plant, respectively, at 189 DAT. The same occurred with the leaf area per plant, plant height and the absolute rate of growth, whose maximum values were 6.183,5 cm², 136.9 cm and 4.4 g/plant/day, respectively. The growth of the plant was continuous throughout the cycle, and the highest amount of dry mass was accumulated in fruits, reaching a marketable production of 97.3 t ha-1. All fruits were classified as Extra.

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The Sedimentary Cycle on Early Mars

Annual Review of Earth and Planetary Sciences ◽

10.1146/annurev-earth-053018-060332 ◽

2019 ◽

Vol 47 (1) ◽

pp. 91-118 ◽

Cited By ~ 16

Author(s):

Scott M. McLennan ◽

John P. Grotzinger ◽

Joel A. Hurowitz ◽

Nicholas J. Tosca

Keyword(s):

Plate Tectonics ◽

Sedimentary Rock ◽

First Order ◽

Sedimentary Environments ◽

Source To Sink ◽

Rock Record ◽

Mineral Assemblages ◽

Sedimentary Cycle ◽

Early Mars ◽

Over Time

Two decades of intensive research have demonstrated that early Mars ([Formula: see text]2 Gyr) had an active sedimentary cycle, including well-preserved stratigraphic records, understandable within a source-to-sink framework with remarkable fidelity. This early cycle exhibits first-order similarities to (e.g., facies relationships, groundwater diagenesis, recycling) and first-order differences from (e.g., greater aeolian versus subaqueous processes, basaltic versus granitic provenance, absence of plate tectonics) Earth's record. Mars’ sedimentary record preserves evidence for progressive desiccation and oxidation of the surface over time, but simple models for the nature and evolution of paleoenvironments (e.g., acid Mars, early warm and wet versus late cold and dry) have given way to the view that, similar to Earth, different climate regimes on Mars coexisted on regional scales and evolved on variable timescales, and redox chemistry played a pivotal role. A major accomplishment of Mars exploration has been to demonstrate that surface and subsurface sedimentary environments were both habitable and capable of preserving any biological record. ▪ Mars has an ancient sedimentary rock record with many similarities to but also many differences from Earth's sedimentary rock record. ▪ Mars’ ancient sedimentary cycle shows a general evolution toward more desiccated and oxidized surficial conditions. ▪ Climatic regimes of early Mars were relatively clement but with regional variations leading to different sedimentary mineral assemblages. ▪ Surface and subsurface sedimentary environments on early Mars were habitable and capable of preserving any biological record that may have existed.

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First-Order Frequency Effects in Supersonic Panel Flutter of Finite Cylindrical Shells

Journal of Applied Mechanics ◽

10.1115/1.3423007 ◽

1973 ◽

Vol 40 (2) ◽

pp. 464-470

Author(s):

M. Holt ◽

T. M. Lee

Keyword(s):

Mach Number ◽

Elastic Shell ◽

Order Effect ◽

Aerodynamic Load ◽

Panel Flutter ◽

Thin Cylindrical Shell ◽

First Order ◽

Flutter Boundary ◽

Shell Equation ◽

Set Up

An improved calculation of the supersonic panel flutter characteristics of a thin cylindrical shell of finite length is presented. The aerodynamic load is determined with account taken of first-order terms in vibration frequency, and when this is introduced into the elastic shell equation an integro differential equation results. An equivalent eigenvalue problem is set up by applying Galerkin’s method to this equation. The flutter boundary, for given Mach number and circumferential mode n, corresponds to the shell thickness ratio at which the real part of any one of the eigenvalues first becomes non-negative. It is found that the most severe flutter condition, for given Mach number, occurs for a circumferential mode n = 7. The present calculations exclude second-order frequency terms in the elastic part of the flutter equation, even though they may have a first-order effect. A subsequent calculation referred to here shows that these terms indeed have no significant influence on the first-order analysis.

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The correlation strength of the most important cryptocurrencies in the bull and bear market

Investment Management and Financial Innovations ◽

10.21511/imfi.17(3).2020.06 ◽

2020 ◽

Vol 17 (3) ◽

pp. 67-81

Author(s):

Sebastian Lahajnar ◽

Alenka Rožanec

Keyword(s):

Correlation Coefficient ◽

Strong Correlation ◽

Pearson Correlation ◽

Pearson Correlation Coefficient ◽

Strongly Correlated ◽

Moderate Correlation ◽

Bear Market ◽

Research Findings ◽

Correlation Strength ◽

Over Time

The article explores the correlation strength of the ten most important cryptocurrencies, emphasizing the examination of differences during the periods of rising and falling prices. The daily and weekly returns of selected cryptocurrencies are taken as the basis for calculating and determining the correlation strength using the Pearson correlation coefficient. The survey covers the period from the beginning of 2017 to Bitcoin’s last local bottom in mid-March 2020. Research findings are as follows: 1) the most important cryptocurrencies are mostly moderately positively correlated with each other over time; 2) correlation strength decreases slightly during the bull period, but mostly remain in the range of moderate correlation; 3) correlation strength increases significantly during the bear period, with most cryptocurrencies strongly correlated with each other. The results do not change significantly if the daily or weekly cryptocurrency returns are used as the basis. A strong correlation in the period of falling prices prevents the effective diversification of the cryptocurrency portfolio, which must be considered when investing funds in the cryptocurrency market.

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Saliva viral load is a dynamic unifying correlate of COVID-19 severity and mortality

10.1101/2021.01.04.21249236 ◽

2021 ◽

Author(s):

Julio Silva ◽

Carolina Lucas ◽

Maria Sundaram ◽

Benjamin Israelow ◽

Patrick Wong ◽

...

Keyword(s):

Viral Load ◽

Disease Severity ◽

T Cell Subsets ◽

Temporal Association ◽

Strongly Correlated ◽

Immunological Parameters ◽

Viral Loads ◽

Patient Demographics ◽

Over Time

While several clinical and immunological parameters correlate with disease severity and mortality in SARS-CoV-2 infection, work remains in identifying unifying correlates of coronavirus disease 2019 (COVID-19) that can be used to guide clinical practice. Here, we examine saliva and nasopharyngeal (NP) viral load over time and correlate them with patient demographics, and cellular and immune profiling. We found that saliva viral load was significantly higher in those with COVID-19 risk factors; that it correlated with increasing levels of disease severity and showed a superior ability over nasopharyngeal viral load as a predictor of mortality over time (AUC=0.90). A comprehensive analysis of immune factors and cell subsets revealed strong predictors of high and low saliva viral load, which were associated with increased disease severity or better overall outcomes, respectively. Saliva viral load was positively associated with many known COVID-19 inflammatory markers such as IL-6, IL-18, IL-10, and CXCL10, as well as type 1 immune response cytokines. Higher saliva viral loads strongly correlated with the progressive depletion of platelets, lymphocytes, and effector T cell subsets including circulating follicular CD4 T cells (cTfh). Anti-spike (S) and anti-receptor binding domain (RBD) IgG levels were negatively correlated with saliva viral load showing a strong temporal association that could help distinguish severity and mortality in COVID-19. Finally, patients with fatal COVID-19 exhibited higher viral loads, which correlated with the depletion of cTfh cells, and lower production of anti-RBD and anti-S IgG levels. Together these results demonstrated that viral load – as measured by saliva but not nasopharyngeal — is a dynamic unifying correlate of disease presentation, severity, and mortality over time.

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BIOM-43. CROSS-PLATFORM ROBUSTNESS IN THE GLUCOCORTICOID RESPONSE PHARMACODYNAMIC BIOMARKER

Neuro-Oncology ◽

10.1093/neuonc/noab196.074 ◽

2021 ◽

Vol 23 (Supplement_6) ◽

pp. vi20-vi20

Author(s):

Emily Tang ◽

John Wiencke ◽

Gayathri Warrier ◽

Helen Hansen ◽

Lucie McCoy ◽

...

Keyword(s):

Association Studies ◽

Elastic Net ◽

Strongly Correlated ◽

Methylation Index ◽

Cpg Sites ◽

Glucocorticoid Response ◽

Cross Platform ◽

Adult Glioma ◽

Epic Array ◽

Over Time

Abstract The neutrophil dexamethasone methylation index (NDMI) is an algorithm-based biomarker to assess individuals’ exposures to dexamethasone, a synthetic glucocorticoid commonly administered for inflammation. Cortisol is the main endogenous glucocorticoid that controls vital processes including the immune response and lipid and carbohydrate metabolism. Variations in the NDMI score reflect individuals’ sensitivities of exposures to both exogenous and endogenous glucocorticoids, and this biomarker was trained using elastic net regression on Illumina’s most recent DNA methylation beadarray, the EPIC array, which contains 850,000 cytosine-guanine (CpG) sites. While technology for microarray research continues to advance over time, researchers are capable of conducting more comprehensive epigenome-wide association studies (EWAS). However, many studies are still run and archived using Illumina’s historical 450K platform with approximately 450,000 CpGs, and there are fewer published databases using the 850K EPIC array. To evaluate the cross-platform bioinformatic comparability, we performed elastic net regression modeling using predictors available in the 450K to train the NDMI. Among the 135 pre-surgery glioma cases from the UCSF Immune Profiles Study (IPS), NDMI scores between the 450K and 850K model were strongly correlated (r = 0.99, p < 0.0001). In the 311 controls from the UCSF Adult Glioma Study (AGS), similar correlations were observed (r = 0.96, p < 0.0001). We observe that NDMI remains a robust tool using historical 450K data and conclude that this algorithmic tool is capable of detecting the variations in individuals’ responses to dexamethasone.

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Characterization of a Fibrin Glue-Gdnf Slow-Release Preparation

Cell Transplantation ◽

10.1177/096368979800700108 ◽

1998 ◽

Vol 7 (1) ◽

pp. 53-61

Author(s):

Henrich Cheng ◽

Matt Fraidakis ◽

Birger Blombäck ◽

Paul Lapchak ◽

Barry Hoffer ◽

...

Keyword(s):

Linear Regression ◽

Least Squares ◽

Fibrin Glue ◽

Trophic Factor ◽

Adult Rats ◽

First Order ◽

First Order Kinetics ◽

Implantation Sites ◽

The Mean ◽

Over Time

One novel method to deliver trophic factor locally in the CNS is to mix it into fibrin glue. In the present studies, [125I]-labeled GDNF-containing fibrin glue balls were used to determine binding and spread of the trophic factor. First, the binding of different concentrations of [125I]-labelèd GDNF in fibrin glue was determined in vitro. Within the six concentrations used (from 200 nM to 0.004 nM, 0 M as control), there was a strong linear correlation between the [125I]-GDNF concentration and the recovered radioactivity (r = 0.992). The mean bound radioactivity in 16 samples with 4 nM [125I]-GDNF was 71262 + 2710 CPM, and accounted for 89.8% of the mean initial count of free [125I]-GDNF (79369 + 3499 CPM). Second, [125I]-GDNF-containing glue balls were implanted into the anterior chamber of adult rats. The implanted fibrin glue balls decreased in size with time, but could still be identified on the irises 2 wk after implantation. Radioactivity was concentrated at the implantation sites in the early stages with a distribution in the surrounding iris tissue, which became separated into focal radioactive spots at the third week. Counts of radioactivity were significantly higher in the [125I]-GDNF glue ball-implanted irises than controls until 14 days after implantation. A study of the [125I] decay over time using least-squares linear regression demonstrated first-order kinetics (r = —0.98, p < 0.02) with k = 0.0091 and T 1/2 = 76 h. Finally, [125I]-GDNF–containing glue balls were implanted in the spinal cord of adult rats. Radioactivity was concentrated at the implantation sites in the early stages and was later distributed more widely in the surrounding thoracic cord. The [125I]-GDNF–containing glue degraded over time and became a porous meshwork with decreasing radioactivity at the later time points. Radioactivity in the spinal cords subjected to implantation of [125I]-GDNF–containing glue balls was higher than in controls for 14 days. Study of the [125I] decay by time with least-squares linear regression demonstrated first-order kinetics (r = -0.97, p = 0.001) with T 1/2 = 75.6 h. We conclude that the trophic factor GDNF becomes bound in the fibrin glue matrix from which it is gradually released. Our results suggest that fibrin glue is an effective substrate for keeping a trophic factor localized in situ for a finite period, protected from the circulation, surrounding aqueous humor or CSF.

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