16 March 2018

Steel-Like Wood

Welcome to Warren’s Notice. Not long after the pyramids were constructed, I obtained a 5-year Bachelor of Civil Engineering. Although I got through an ungodly number of courses to rack up 180 credit hours, I never had a course in materials science.

That I missed or didn’t appreciate advances in wood science and technology over the years is a testament to that gap in my education. But even I’m amazed at the latest advance.

A team of researchers from Maryland, California Merced and Northeastern universities and the USDA Forest Service developed a way to transform wood into a product that’s about as strong as steel.

Structural Materials
Wood has a lot going for it as a structural material: It’s abundant, renewable and inexpensive, and it boasts a history of use dating back to the Stone Age. On the other hand, wood isn’t going to win prizes for strength, at least when compared to synthetic materials like steel.

That said, the drawbacks of steel or alloys include weight and environmental impact, while composites require complex, costly manufacturing processes.

So, for wood to win in all categories, all you’ve got to do is make it stronger without affecting its other properties or impacting the environment. 

Tree cross section: 1-pith, 2-heartwood, 3-sapwood, 4-cambiumm layer, 5-bast fibre, 6-bark, 7-annual rings, 8-spring growth, 9-autumn growth, 10-medullary rays (from www.boeingconsult.com/tafe/mat/Timber/HowTreeGrows-OH.htm).
A Closer Look at Wood
Wood, like all plants, is composed of cells. Look at a newly cut tree stump. The lighter colored sapwood near the outer edge has tubular xylem that transport water and nutrients from roots to leaves. The sapwood encircles the darker, dead heartwood, in which the xylem have filled with resin or gums.

Although xylem contain other cell types, the most distinctive are the long tracheids, primarily in softwood species, and the somewhat more visible vessel elements that are predominant in hardwood species.

Softwood (L) and hardwood tree cell structure, magnified 50 times (from www.boeingconsult.com/tafe/mat/Timber/HowTreeGrows-OH.htm).
Wood cells consist of cellulose (about 50%), lignin (about 20% to 25% in hardwoods, 25% to 33% in softwoods) and hemicellulose (the residual). In general, cellulose is wood’s fibrous bulk. Lignin holds the fibers together, filling the cell wall spaces between cellulose and hemicellulose and conferring mechanical strength as well as a more hydrophobic barrier for water transport.

Softwood (L) and hardwood tree cell structure, magnified 250 times (from www.boeingconsult.com/tafe/mat/Timber/HowTreeGrows-OH.htm).
Beefing Up Wood
Over the years, different studies have had limited success devising processes to increase wood density and strength. Pretreatment with steam, heat, ammonia or cold rolling followed by densification has improved mechanical performance but resulted in incomplete densification and a lack of dimensional stability.

For their breakthrough solution, the researchers developed a two-step process: (1) boil the wood in an aqueous mixture of sodium hydroxide and sodium sulfite to remove just the right amount of lignin and hemicellulose, then (2) compress the wood between metal plates heated to 100°Celsius at a pressure of 725 pounds/square inch (5 megapascals) to remove most of the xylem tubes (vessel elements and tracheids).

Wrap Up
The resulting processed wood is about 80% thinner and has triple the density; more than a tenfold increase in strength, toughness and ballistic resistance; and greater dimensional stability. The final product is about as strong as steel though six times lighter weight. Its specific strength (strength/density) is higher than that of most structural metals and alloys.

Scanning electron microscopy images of wood before (L) and after processing to increase density and strength (from www.nature.com/articles/nature25476).
With its higher density, the processed wood will not float on water but neither does it swell much on contact with water.

Overall, the resulting materials and their laminates are relatively easy to produce. The process is applicable with various tree species and, with reasonable care, the chemicals pose no significant environmental concern.

As I wrote, even I can see that wood has come a long way. Thanks for stopping by.

Background articles on wood:
Study on new process to increase wood strength and article on study, both in Nature:
Articles on study on ScienceNews and ScienceDaily websites:

09 March 2018

Gun Research Revisited

Welcome to Warren’s Notice. Guns are in the news again. We’re again debating what can and should be done. I hope you won’t mind if I repeat my pitch for gun research, not gun control, this time with some big-league help.

National Rifle
Association logo.
Earlier Gun Blog Post 
If perchance you missed it, I blogged about the topic a year ago (Gun Research). I noted that the National Rifle Association, once appreciated by all for gun safety education, marksmanship training and shooting for recreation, didn’t evolve into the gun-rights lobbying organization until the 1970s.

Presumably in response to lobbying, Congress removed funding for gun violence research by the Centers for Disease Control and Prevention in 1996 and, in 1997, prohibited the CDC from spending funds “to advocate or promote gun control.” Though not a ban per se, it made it inadvisable for the CDC to fund any gun research.

Lest the message be missed, Congress later applied the same funding constraint on the National Institutes of Health.

Gun research has continued without federal support; however, the funding and research publications are small fractions of what would be expected based on statistics for other leading causes of death.

Gun Storage Safety
In my earlier blog post, I gave examples of then recently published studies to indicate what could be learned through research. For this post, I thought the recent study by researchers from the Johns Hopkins Bloomberg School of Public Health would be convincing.

They surveyed 1444 gun owners in 2016 and found less than half (46%) stored all of their guns safely--in a locked gun safe, cabinet or case; locked into a gun rack; or stored with a trigger lock or other lock.

One of many types of firearm safe storage solutions (from www.sportsmansguide.com/product/index/secure-it-handgun-storage-safe?a=282585)
The primary factors driving safe storage were having a child in the home, especially any younger than 18; owning only handguns; or being influenced by family discussions or a gun safety course.

Along with highlighting a safety problem, the study pointed toward a solution. The gun owners ranked law enforcement, hunting or outdoors groups, active-duty military, military veterans and the NRA as most effective in communicating safe storage practices, with each cited by at least 70% of the survey respondents.

RAND Corporation
Rand Report
While my research pitch won’t be seen beyond my small circle of readers, the RAND Corporation, the nonprofit, nonpartisan think tank, just released a report on its two-year Gun Policy in America initiative.

That research addressed two questions:
1. What does the scientific evidence say about the effects of various firearm policies on societally important outcomes?
2. What steps might policymakers and other stakeholders take to improve the scientific evidence base on how gun policies affect outcomes?

RAND’s Key Findings
The overriding finding is that the available data support few conclusions. Of the many studies reviewed, only 62 went beyond correlations to laws causing results.

The evidence does support the conclusion that safe-storage laws reduce fatal or nonfatal injuries among youth and children.

Other moderately supported findings are:
- background checks reduce firearm suicides and homicides,
- stand-your-ground laws may increase homicide rates, and
- prohibiting gun purchase or possession by individuals who have a history of involuntary commitment to a psychiatric facility reduces violent crime.

RAND’s Research Recommendations
Among RAND’s recommendations were those regarding research:

Congress should consider lifting restrictions that limit research funding and access to data. The administration should invest in firearm research at the CDC, NIH and National Institute of Justice at levels comparable to its investment in other threats to public safety and health.

Government and research sponsors should support research examining the effects of gun laws on a wider set of outcomes, including crime, defensive gun use, hunting and sport shooting, officer-involved shootings and the gun industry.

Congress should consider eliminating restrictions it imposed on the use of gun trace data for research.

Wrap Up
If you’ve interest in the topic, the RAND report should be atop your reading list.

Expanding on safe storage, I see value in studying the effects of requiring safety training as some states do. RAND’s look at licensing and permitting requirements was, at best, inconclusive and didn’t appear to address training.

If you have ideas for research, pass them to your state and federal representatives. Thanks for stopping by.

Study on gun storage practices in American Journal of Public Health: ajph.aphapublications.org/doi/10.2105/AJPH.2017.304262
Examples of articles on study: 

RAND’s Gun Policy in America initiative: www.rand.org/research/gun-policy.html
RAND’s Synthesis of research evidence on the effects of gun policies: www.rand.org/pubs/research_reports/RR2088.html
Examples of articles on RAND study:
Firearm licensing and training: lawcenter.giffords.org/gun-laws/policy-areas/gun-owner-responsibilities/licensing/

02 March 2018

Ethics Weighs Competence

Welcome to Warren’s Notice. I’ve a new one for you to ponder: Do we perceive unethical people as less competent? Here’s a hint: Yes.

Does unethical behavior influence
perceived competence?
(photo from multiple websites)
A recently published report by researchers from Toronto and Stanford universities found that, while most people thought moral behavior and competence were independent, information about someone’s morality did in fact influence their judgment of the person’s competence.

Effects of Immorality on Perception
The researchers began with a pilot study that had 98 participants evaluate the job competence of a doctor, waiter and engineer based mainly on the individuals’ job preparation and performance. The participants were also advised of the individuals’ past immoral behavior (shoplifting, neglecting elderly parent, cheating on spouse) and asked if that behavior told them anything about job competence.

Although it varied with the circumstance, no less than 80% of the participants indicated that moral information was irrelevant to judgments of job competence--it would not affect their judgment.

But when comparisons with control or moral individuals were made in six follow-up studies involving 1567 participants, people were judged to be less competent if they committed hypothetical transgressions, cheated on lab tasks, acted selfishly in economic games or received low morality ratings from coworkers.

In one study, for example, 155 participants rated an individual’s job competence after learning he had either cheated or refrained from cheating to win money or after receiving no information about cheating (control).

The studies were designed to ensure insofar as possible the participants’ judgements would be based on morality and not caused by impressions of warmth or a halo effect (i.e., less well-liked individuals being perceived as worse in every way, including competence).

Effect of Social Intelligence
Of particular interest is the researchers’ hypothesis that immoral individuals are seen as less competent because their immoral actions cause them to be viewed as low in social intelligence. They defined social intelligence as how effectively one negotiates complex social relationships (interacting with people, perceiving others’ thoughts and feelings, inferring social rules and norms).

In one key study, 205 participants saw a picture of a male and were given the individual’s demographic information along with ten coworkers’ average ratings of his conscientiousness, openness and optimism. Participants were also randomly assigned to receive either high or low ratings of the individual’s morality.

To gauge the effect of social intelligence, the participants were then randomly assigned either to learn their individual was rated high on social intelligence or receive no further information.

Participants that received no information on social intelligence rated the immoral individual as significantly less competent than the moral individual. Yet participants that learned the individual was highly socially intelligent rated the immoral and moral individuals’ competence the same.

Wrap Up
Social intelligence seems to mediate the link between moral information and perceptions of competence.

Immoral individuals with high social intelligence may be perceived as highly competent; however, that competence could be in using their social intelligence abilities for their own advantage in a selfish strategic manner.

It makes you wonder how this carries over to politicians. Thanks for stopping by.

Study of morality effects on perception of competence in Journal of Personality and Social Psychology: psycnet.apa.org/record/2018-03783-001
Article on study on ScienceDaily website:
American Psychological Association press release on study:

23 February 2018

Science Status Report

Welcome to Warren’s Notice. Having worked in science and engineering (S&E) for more than half a century, I find it difficult to accept that I now have to march to defend science. Nevertheless, I did participate in last April’s March for Science, as I blogged in Marching for Science; and considering what’s happening in Washington, I may be marching again this year.

But this blog post isn’t about me or marching; it’s about a report. Last month, the National Science Foundation--the federal agency that supports fundamental research and education in non-medical S&E--released Science & Engineering Indicators 2018. The NSF’s governing National Science Board is congressionally mandated to report the status of U.S. S&E every two years.

Chapters of NSF Science & Engineering
Indicators 2018 report.
Although the report is based mainly on data collected through 2015 or 2016, it still offers unique and useful background for assessing where we are and where we’re headed.

NSF Report
The online, interactive report is loaded with clearly presented, wide-ranging data and commentary. Included for separate, easy access with the full report are a digest; the data; the figures; trends in S&E by state; sources of U.S. research and development (R&D) expenditures; as well as a further breakdown of other report content.

Cover of NSF Science &
Engineering Indicators
 2018 report digest.
The digest is particularly useful, serving in effect as an executive summary that introduces the report, highlights important trends and links to the available data. It focuses on 42 indicators under 7 themes, 3 of which are viewed globally--R&D spending; research outputs; and science, technology, engineering and math (STEM) education--and 4 of which are viewed domestically--R&D funding and performance; the S&E workforce; invention, knowledge transfer and innovation; and public attitudes and understanding of science and technology.

Principal Finding
The big news is that, while the U.S. holds a preeminent global position in S&E, the lead is shrinking. Other nations, especially China, increasingly recognize scientific and technical capabilities as engines of economic growth.

Between 2000 and 2015, China, India and South Korea expanded R&D expenditures rapidly compared to the pace of the U.S and European Union (E.U.). In 2015, the U.S. accounted for 26% of global R&D expenditures; China accounted for 21% of the total.

Percentage of Global R&D expenditures by region in 2000 and 2015 (from NSF Science & Engineering Indicators 2018).

R&D improves production processes in manufacturing and services, a major component of the global economy. China has grown to become the largest global producer in medium-high-technology manufacturing industries and second only to the U.S. in high-technology manufacturing industries.

Research publications contribute to knowledge. In 2016, China produced the largest number of articles in engineering, chemistry, physics, geosciences, computer sciences and agricultural sciences.

Over the past 15 years, nearly half of the S&E bachelor’s degrees awarded globally were conferred in India (25%) and China (22%), compared to 10% in the U.S.

Changes Ahead
Permit me to select data on a few areas that will almost certainly see significant change with the current administration--defense, sustainable energy and immigration.

Defense’s share of the federal R&D budget was anomalously low in 2009 (52%), but since 2010 it has gradually declined (58% to 53%). Expect that to zoom ahead.

The large investment and deployment of sustainable energy technologies grew renewable energy generation capacity from 130 gigawatts (GW) in 2006 to 912 GW in 2016, excluding hydropower. Between 2010 and 2016, China added a cumulative 200 GW of solar and wind generation capacity, the E.U. added a cumulative 137 GW and the U.S. added much less, 82 GW. It’s likely the U.S. will continue to lag.

Foreign-born scientists and engineers are critical to the U.S. S&E workforce--41% of master’s degree holders, 36% of PhDs and over half of PhDs in engineering, computer sciences and mathematics occupations are foreign born. The squeeze on immigration is already having an effect. The number of international students in the U.S., which was climbing steadily, dropped in 2017 in nearly all areas. The largest graduate student declines were in computer science and engineering.

Wrap Up
I’ve been living in Wisconsin for the past few years, though my ties are stronger to New York and Virginia. As an example of the state-specific data available in the report and the way it can be manipulated, I compared the percentage of bachelor’s degree holders among individuals 25-44 years old in the U.S. and each state.

Percentage of bachelor’s degree holders among individuals 25-44 years old in U.S., New York, Virginia and Wisconsin, 2005-2016 (derived from data in NSF Science & Engineering Indicators 2018).
I strongly recommend you take a look at the report. I’m sure you’ll come up with something much more significant. Thanks for stopping by.

NSF’s Science & Engineering Indicators 2018 report: www.nsf.gov/statistics/2018/nsb20181/
Article on report on ScienceDaily website: www.sciencedaily.com/releases/2018/01/180124113951.htm