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A review covering a synopsis of the history of forest sustainability concepts and how it has led to the social, economic, and legal frameworks, criteria and indicators, and key incentive programs, which promote and influence conservation and sustainable management of forests in the United States of America is presented in two parts. The main findings show that the United States of America is a world leader in sustainable forest management, demonstrated by the fact that since the beginning of the 20th Century, forest area has been relatively stable although the population has increased, and the country remains one of the top timber producers in the world. Sustainable forest management in the United States of America is achieved in the context of private and public ownership, stakeholder collaboration, a federalist system with overarching federal laws that give freedom to state and local jurisdictions to use regulatory and voluntary means to achieve those aims, and a variety of government incentive programs offering technical assistance, financial assistance, and tax relief for landowners who proactively practice responsible forest management. This framework is reinforced through consistent enforcement of laws, monitoring, and reporting of changing conditions, and an array of future modeling to inform management actions. [ABSTRACT FROM AUTHOR]

The forest industry is a significant contributor to many local and state economies in the United States (US). Informed public policy at state and national levels requires that decision makers have accurate and defensible information on the value and structure of these economic contributions. However, different methods and modeling assumptions used and different industry sectors included by various analysts complicate meaningful comparisons across regions and time. This work presents a standardized approach to economic contribution assessments of the forest industry. The US Southern Forest region serves as an example of this approach with standardized results for economic contributions per capita, per acre of timberland, and per unit volume of timber harvested when comparing across regions and time. Among other findings, the results suggest that states with developed wood and paper product manufacturing industries have significantly greater economic contributions than states that are concentrated on timber harvesting. [ABSTRACT FROM AUTHOR]

Numerous forests in the eastern United States have been degraded due to past exploitative timber harvesting known as high grading. High graded forest stands may not improve without active rehabilitation and may require targeted silvicultural treatments. This study focuses on high graded mixed-oak (mixed- Quercus spp.) stands and aims to develop a model that can identify past high grading and to determine modifications that may improve forest management recommendations provided by the prominent decision support tool, SILVAH. We present a model that uses standard forest inventory measurements and does not require knowledge of preharvest stand conditions to predict with moderate to high accuracy whether a stand was high graded, which could be particularly useful for nonindustrial private forests. Results indicate that modifications to SILVAH may be necessary to improve its utility for prescribing silvicultural treatments in high graded stands. [ABSTRACT FROM AUTHOR]

• Mixed-oak stands of similar stand densities can vary vastly in structure, composition, and biomass and carbon storage. • High graded stands are of particular concern due to potential negative effects on future forest health and sustainability. • High graded forest characteristics are compared to those of a well-established silvicultural treatment. • High graded mixed-oak forests contained more unhealthy and/or poorly-formed trees, more small diameter trees, and fewer tree seedlings. • High graded mixed-oak forests stored less aboveground biomass and carbon per hectare. Forests of the eastern United States (US) mostly comprise a mix of stands managed following silvicultural principles and stands managed with exploitative timber harvesting practices. These stands can have similar stand densities (e.g., basal area per hectare) but vary vastly in structure, composition, and biomass and carbon storage. High grading, a prevalent exploitative timber harvesting practice in the eastern US, is of particular concern because it can negatively affect future forest health and productivity. This study quantifies differences in forest structure, composition, and biomass and carbon storage between high graded stands and stands that received a seed/establishment cut of a uniform shelterwood regeneration sequence treatment, which is a comparable and well-established silvicultural method used to regenerate mixed-oak forests. It focuses on mixed-oak forests (mixed- Quercus), where the effects of high grading have been understudied, and uses a sample with broader spatial coverage than previous studies. The sample comprised nine stands that were known to have been high graded 8–15 years ago and nine stands that received the seed/establishment cut of a uniform shelterwood regeneration sequence. Stand were systematically sampled using fixed-area plots. Field measurements were collected and used to calculate metrics describing forest structure and function. The structure of high graded stands was characterized by a higher proportion of trees with poor health and/or form compared to shelterwood stands, with 18.3 % less acceptable growing stock and trees with lower crown compaction. Diameter distributions of high graded stands were characterized by numerous small trees and few large-diameter trees. Spatial variability of overstory trees was contingent on the tree size range evaluated, with a larger variability of sawtimber-sized trees (trees ≥ 29.2 cm in diameter at breast height) in high graded stands. High graded stands also had 2.2 times fewer oak trees (Quercus spp.) in the overstory canopy, 17,897 fewer seedlings per hectare (ha), and 45 Mg/ha less biomass than shelterwood stands. These results indicate that high grading generally degrades mixed-oak forests and impairs their long-term capacity to supply vital ecosystem services such as habitat for specific wildlife species, carbon storage, and high-quality wood products. [ABSTRACT FROM AUTHOR]

The roofing of buildings in which a vaulted or domed ceiling projects above the level of the wall plate presents a structural problem because a continuous tie beam cannot be used. British and American carpenters adopted quite different solutions to this problem. The British solution was to use a raised tie beam, and variations on this theme were adopted by a number of carpenters from the seventeenth to the nineteenth centuries. It also appears in both British and American carpenters' manuals. In the roof structures of a number of Connecticut churches, however, the tie beam is divided and arranged in the form of a scissors. This type of structure has a structural advantage when used in association with light walls of brick or timber. These roofs form a group associated with Ithiel Town, who was probably responsible for the design. [ABSTRACT FROM AUTHOR]

A cloud-based software, VirtualDose-IR (Virtual Phantoms Inc., Albany, New York, USA), designed to report organ doses and effective doses for a diverse patient population from interventional radiology (IR) procedures has been developed and tested. This software is based on a comprehensive database of Monte Carlo-generated organ dose built with a set of 21 anatomically realistic patient phantoms. The patient types included in this database are both male and female people with different ages reflecting reference adults, obese people with different BMIs and pregnant women at different gestational stages. Selectable parameters such as patient type, tube voltage, filtration thickness, beam direction, field size, and irradiation site are also considered in VirtualDose-IR. The software has been implemented using the ‘Software as a Service (SaaS)’ delivery concept permitting simultaneous multi-user, multi-platform access without requiring local installation. The patient doses resulting from different target sites and patient populations were reported using the VirtualDose-IR system. The patient doses under different source to surface distances (SSD) and beam angles calculated by VirtualDose-IR and Monte Carlo simulations were compared. For most organs, the dose differences between VirtualDose-IR results and Monte Carlo results were less than 0.3 mGy at 15 000 mGy * cm2 kerma-area product (KAP). The organ dose results were compared with measurement data previously reported in literatures. The doses to organs that were located within the irradiation field match closely with experimental measurement data. The differences in the effective dose values between calculated using VirtualDose-IR and those measured were less than 2.5%. The dose errors of most organs between VirtualDose-IR and literature results were less than 40%. These results validate the accuracy of organ doses reported by VirtualDose-IR. With the inclusion of pre-specified clinical IR examination parameters (such as beam direction, target location, field of view and beam quality) and the latest anatomically realistic patient phantoms in Monte Carlo simulations, VirtualDose-IR provides users with accurate dose information in order to systematically compare, evaluate, and optimize IR plans. [ABSTRACT FROM AUTHOR]

This article focuses on Willie Drake's business of reusing old wood beams. Drake's company, Mountain Lumber, deals with salvage lumber from large factory warehouses in the U.S. The business has grown as high-end home builders started looking for wood that is denser and of higher quality. In Drake's lumber yard, workmen labor over old boards and make them straight again. Drake sells the boards several times the price of new wood paneling.