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The new Shakespeare Memorial Theatre in Stratford-upon-Avon was opened by the Prince of Wales on the playwright's traditional birthday in 1932; Charles Flower's original building had been ravaged by fire [...]

When I was a child, we didn't have a matched set of china. Maybe there had been one before I was born, but pieces had broken or just plain disappeared [...]

This article summarizes recent work at the site of Las Chachalacas, located in the Municipio of Quiriego, southern Sonora. Set within the western foothills of the Sierra Madre Occidental, Las Chachalacas was adjacent to an arroyo that periodically became impounded, producing a marsh like environment. Stratigraphic associations and a minimal number of 14C dates suggest the site was regularly utilized from the terminal Pleistocene through the Early Agricultural period. Results contribute to several enduring debates in the North American Southwest regarding Pleistocene landscape use, demographic continuity through the Holocene Climatic Optimum (7500–5000 cal BP), the sequence of mobility and subsistence changes in the Archaic/Early Agricultural periods, and the identities of the earliest farmers indexed by material culture such as projectile points.

Cocrystallizing a given molecule with another can be useful for adjusting the physical properties of molecules in the solid state. However, most combinations of molecules do not readily cocrystallize but form either one-component crystals or amorphous solids. Computational methods of crystal structure prediction can, in principle, identify the thermodynamically stable cocrystal and thus predict if molecules will cocrystallize or not. However, the pronounced polymorphism and tendency of many organic molecules to form disordered solids suggest that kinetic factors can play an important role in cocrystallization. The question remains: if a binary system of molecules has a thermodynamically stable cocrystal, will it indeed cocrystallize? To address this question, we simulate the crystallization of more than 2600 distinct pairs of chiral model molecules of similar size in 2D and calculate accurate crystal energy landscapes for all of them. Our analysis shows that thermodynamic criteria alone are unreliable in the prediction of cocrystallization. While the vast majority of cocrystals that form in our simulations are thermodynamically favorable, most coformer systems that have a thermodynamically stable cocrystal do not cocrystallize. We furthermore show that cocrystallization rates increase 3-fold when coformers are used that do not form well-ordered single-component crystals. Our results suggest that kinetic factors of cocrystallization are decisive in many cases.

Before the colonial period, California harboured more language variation than all of Europe, and linguistic and archaeological analyses have led to many hypotheses to explain this diversity1. We report genome-wide data from 79 ancient individuals from California and 40 ancient individuals from Northern Mexico dating to 7,400–200 years before present (bp). Our analyses document long-term genetic continuity between people living on the Northern Channel Islands of California and the adjacent Santa Barbara mainland coast from 7,400 years bpto modern Chumash groups represented by individuals who lived around 200 years bp. The distinctive genetic lineages that characterize present-day and ancient people from Northwest Mexico increased in frequency in Southern and Central California by 5,200 years bp, providing evidence for northward migrations that are candidates for spreading Uto-Aztecan languages before the dispersal of maize agriculture from Mexico2–4. Individuals from Baja California share more alleles with the earliest individual from Central California in the dataset than with later individuals from Central California, potentially reflecting an earlier linguistic substrate, whose impact on local ancestry was diluted by later migrations from inland regions1,5. After 1,600 years bp, ancient individuals from the Channel Islands lived in communities with effective sizes similar to those in pre-agricultural Caribbean and Patagonia, and smaller than those on the California mainland and in sampled regions of Mexico.

This work examines the feasibility of joining two dissimilar metals, vanadium (V) and wrought Nitronic 40 stainless steel, through electron beam additive manufacturing (EBAM). Depositing V on Nitronic 40 led to mixed results with some builds exhibiting microcracking and other builds exhibiting severe cracking resulting in delamination. These build failures are thought to be caused by a large coefficient of thermal expansion (CTE) mismatch and solubility issues, demonstrating the challenges associated with this material combination. The large melting temperature discrepancy between Nitronic 40 and V was thought to exacerbate the issues with CTE mismatch and solubility. Four strategies could be employed by EBAM to mitigate the observed issues to successfully deposit V on Nitronic 40: (1) adjust wire feed speed, (2) use dual wire feeders, (3) use different wire feedstocks to control composition, and (4) create a transition layer known as buttering to accommodate CTE mismatch.

The Huatabampo tradition was first defined by Gordon Ekholm, in 1938, and refers to those sites in the coastal plain in northern Sinaloa and southern Sonora lacking architecture but containing well-manufactured plain ceramics with complex shapes. Recent investigations in the region are helping to refine the chronology, geographical extension, cultural attributes, and ethnicity. With 20 radiocarbon dates, we can place this tradition as spanning from 200 BC to AD 1450. The maximum geographical extension ranges from the Middle Rio Yaqui in the north to the Rio San Lorenzo in Sinaloa. The associated sites of this complex are represented by dispersed houses, indicative of ranchería-type settlements, funerary mounds, shell middens, and petroglyph sites. At about AD 1150, Aztatlán pottery and other commodities from southern Sinaloa were incorporated mostly as mortuary offerings. We also provide evidence that the Huatabampo archaeological tradition is a local culture representing the occupation of the Cahitan-speaking groups, Yoremem/Mayos and Yoemem/Yaquis, of the coastal plain.

This article revises the spatial and temporal boundaries of the Casas Grandes tradition associated with northwest Chihuahua, Mexico, based on new data collected in neighboring northeastern Sonora. The Casas Grandes tradition attained its greatest extent during the Medio period (AD 1200–1450/1500) followed by a dramatic demographic and political collapse. Hunter-gatherer groups subsequently occupied most of northwest Chihuahua. Data from the Fronteras Valley, Sonora, presents an alternative scenario, with a clear pattern of cultural continuity from the eleventh century to the colonial period in which sedentary farmers occupied the same landscapes and occasionally the same villages. These observations contribute to our understanding of the spread and subsequent demise of the Casas Grandes tradition in hinterland regions. For the Fronteras Valley, we infer that immigrant groups originally introduced Casas Grandes traditions and that uneven participation in a suite of shared religious beliefs and practices was common to all the hinterlands.

Purpose: To assess the variability of silicone oil (SO) particles released across syringes from the same lot and the role of different needle gauges.Materials and methods: Four syringe models and six needle models were assessed for SO release. About 50 microliters of a buffer solution were loaded into the syringe, needle or syringe/needle setup. The data were analyzed by imaging flow cytometry with fluorescently labeling for SO.Results: All syringe models had a high coefficient of variation in SO release across syringes from the same lot. The amount of SO was significantly greater in the syringe when the needle was attached. SO particles with the BD 30G needle attached to the syringe were statistically greater than the 27G counterpart (p= 0.005). None of the other comparisons was statistically different. Finally, the number of SO particles was higher in the syringe/needle setup than in needles only (p= 0.0024).Conclusion: We found a high variability in SO content across syringes from the same lot. Additionally, there was no clear association between needle gauge and the number of SO particles, as well as their coefficient of variation. Finally, the needles accounted for a small number of SO particles in comparison to the combined syringe-needle setup.

Previous experiences have shown the effectiveness of the zero tolerance program implemented by the San Diego State University's Dept of Public Safety. The program ensures the maintenance of a quality police force through proper selection, training and performance evaluation. In addition, workplace violence workshops and meetings are regularly held between the security personnel, the faculty and the staff., The violent shooting of three faculty members has taught San Diego State University security the importance of zero tolerance. On August 15, 1996, a graduate student at San Diego State [...]

Kinetics can play an important role in the crystallization of molecules and can give rise to polymorphism, the tendency of molecules to form more than one crystal structure. Current computational methods of crystal structure prediction, however, focus almost exclusively on identifying the thermodynamically stable polymorph. Kinetic factors of nucleation and growth are often neglected because the underlying microscopic processes can be complex and accurate rate calculations are numerically cumbersome. In this work, we use molecular dynamics computer simulations to study simple molecular models that reproduce the crystallization behavior of real chiral molecules, including the formation of enantiopure and racemic crystals, as well as polymorphism. A significant fraction of these molecules forms crystals that do not have the lowest free energy. We demonstrate that at high supersaturation crystal formation can be accurately predicted by considering the similarities between oligomeric species in solution and molecular motifs in the crystal structure. For the case of racemic mixtures, we even find that knowledge of crystal free energies is not necessary and kinetic considerations are sufficient to determine if the system will undergo spontaneous chiral separation. Our results suggest conceptually simple ways of improving current crystal structure prediction methods.

Americans with Disabilities Act (ADA) improved public transit systems by reducing noise levels introducing simple traffic routes and signals and having trained staff to handle emergency situations, to accommodate people with cognitive disabilities. Para-transit systems are used when the passengers are unable to board or disembark from the vehicle without help. The ADA provides individual guides and special travel training programs for the disabled people to familiarize themselves with transportation.

Estate planning lawyers and accountants--beware! The proposed federal budget for the 2010 fiscal year allocates $5.5 billion toward the enforcement of federal tax laws, representing a $400 million increase in [...]

This article summarizes research conducted in the Sahuaripa and Bacanora valleys of Sonora, Mexico. Located in the Serrana culture area of the Sierra Madre Occidental, data from this region speaks to several prevalent debates regarding the precolonial era of Northwest Mexico. Radiocarbon dates support demographic reconstructions for sizeable populations post-1000 AD; a time when other regions of the Northwest/Southwest (NW/SW) experienced significant demographic changes. Material cultural patterns reflect substantial local and regional connections with neighboring Río Sonora groups and Huatabampo. Recovered polychrome ceramics demonstrate long-distance connections with Casas Grandes, and obsidian data reflect connections to the Sonora and other neighboring valleys. These data indicate the Sahuaripa Valley participated in a corridor of exchange, which potentially included interaction between Casas Grandes and West Mexico. These observations are relevant to macro-scale patterns of interaction in the late-precolonial NW/SW.

Certain factors may increase the risk of disease of the coronary arteries, the major blood vessels supplying the heart. These risk factors were evaluated in excessively overweight women with normal blood glucose levels, impaired glucose tolerance (IGT; the inability of the body to absorb and use glucose), and non-insulin-dependent diabetes mellitus (NIDDM). The numbers of patients in the groups were 14, 8, and 14, respectively. The women were assessed before and after gastric bypass surgery, an operation to bypass the stomach. In comparison with 10 lean women of similar age, before surgery the obese women had blood lipid and apolipoprotein levels that tended to be atherogenic. (Atherogenic refers to the ability to cause atherosclerosis, the accumulation of lipids and overgrowth of cells within blood vessels, which obstructs blood flow.) The smaller and more dense low-density-lipoprotein (LDL) particles in obese women with IGT or NIDDM may also contribute to the risk for coronary heart disease (CHD). A decrease in size of LDL particles is correlated with increases in blood insulin levels. The body mass index, blood insulin levels, and triglyceride levels decreased and LDL size increased after gastric bypass surgery. In addition, high-density-lipoprotein (HDL; which is believed to have a protective effect in preventing CHD) was increased in all the women following surgery. Changes in the properties of LDL appear to be beneficial in reducing the risk of coronary heart disease in obese women with IGT or NIDDM. (Consumer Summary produced by Reliance Medical Information, Inc.)

Are you using the technology you have to its fullest potential? Computerization in business is moving into its second phase. No longer are companies pondering the question of computers in [...]

The article discusses about the Puritanism & the Ideological Founding of America. Topics of discussion includes the origin of the United States does not starts on the Declaration of Independence signed in 1776 but on the arrival of the first African slaves in Virginia in 1619 that places the consequences of slavery and the contributions of black Americans in the limelight of the nations but questions the founding of Jamestown 12 year prior to Virginia.

South Korea’s public service broadcasting sector comprises a unique combination of editorial independence and government influence, which primarily rises from the South Korean president’s authority to appoint key media figures in the public sector. While this does not necessarily lead to restraints on freedom of speech, it leaves public service broadcasters (PSBs) vulnerable to interference when those at the top of government seek to shape media content and editorial tone. A study of the years 2008–2017 demonstrates one such case, in which former Presidents Lee Myung Bak and Park Geun Hey used the power of appointment to steer PSB news content in favor of their respective administrations. The reactions among PSB journalists and staff show they actively resist the government when they feel their independence is compromised. The paper concludes that such resistance is of limited effect as long as the power of appointment lies in the hands of the president. Only policy change that grants complete independence can guarantee freedom of speech among public broadcasters in South Korea.

Predicting the crystallization of chiral molecules from solution is a major challenge in the chemical sciences. In this paper, we use molecular dynamics computer simulations to study the crystallization of a family of coarse-grained models of chiral molecules with a broad range of molecular shapes and interactions. Our simulations reproduce the experimental crystallization behavior of real chiral molecules, including racemic and enantiopure crystals, as well as amorphous solids. Using efficient algorithms for the packing of shapes, we enumerate millions of low-energy crystal structures for each model and analyze the thermodynamic landscape of polymorphs. In agreement with recent conjectures, our analysis shows that the ease of crystallization is largely determined by the number of competing polymorphs with low free energy. We find that this number and, hence, crystallization outcomes depend on molecular interactions in a simple way: Strongly heterogeneous interactions across molecules promote crystallization and favor the spontaneous resolution of racemic mixtures. Our results help rationalize a number of experimental observations and can provide guidance for the design of molecules and experimental conditions for desired crystallization outcomes.

The construction of the $780-million San Joaquin Hills Transportation Corridor in Orange County, CA, is the biggest public highway project in the history of the US. The 17.5-mile project was undertaken by the California Corridor Constructors, a joint venture between the Granite Construction Co and the Kiewit Pacific Co. The Corridor is unique because it was accomplished on time, on budget and safely despite a tight schedule, environmental constraints and floods., The massive San Joaquin Hills Transportation Corridor is the largest publicly bid highway project in history - one that was constructed on budget, on-time, and most importantly, safely. The Corridor [...]

In some cases, breast cancer patients receive adjuvant chemotherapy after surgical removal of their cancer. The rationale is to destroy any microscopic deposits of cancer cells that may be outside the primary area removed during surgery. In a recent case, a 35-year-old woman, developed severe toxic effects in response to the adjuvant chemotherapy that consisted of cyclophosphamide, methotrexate, and 5-fluorouracil (5-FU). The patient developed severe gastrointestinal symptoms including stomatitis and diarrhea as well as mild neurologic symptoms including difficulties with balance and spelling simple words. The patient had abnormally low levels of white blood cells. The toxic reaction was found to be the result of a genetic defect that made this patient susceptible to toxic effects of 5-FU, even at normal doses. The patient was found to have a deficiency in the enzyme dihydropyrimidine dehydrogenase (DPD); further evaluation revealed that both her mother and father carried a single defective gene for this enzyme. The case illustrates how an unsuspected genetic trait may affect the response to a drug. The drug 5-FU is a pyrimidine analog. It is similar in chemical structure to pyrimidines, such as thymine and cytosine, which are normally converted into substances called nucleotides in preparation for incorporation into DNA structure. When 5-FU is administered to a patient, less than 20 percent is metabolically converted into analogous, but toxic, nucleotides. The remainder is metabolically destroyed by DPD. Therefore, a deficiency of DPD results in a much higher amount of toxic 5-FU by-products. In the present case, the removal of 5-FU from the chemotherapeutic regimen solved the problem, and the patient is now healthy and free of signs of cancer. Since severe toxic reactions may result from an enzyme deficiency, patients showing such reactions should be tested for enzyme activities. Unrecognized DPD deficiency may be more common than previously suspected. (Consumer Summary produced by Reliance Medical Information, Inc.)

Nanostructured catalysts for low-temperature ammonia synthesis have been developed viathermal treatment under nitrogen of Ru-containing MOFs. The resulting catalysts reveal high concentration of small Ru nanocrystals (<4 nm) well-dispersed on a graphitic carbon shell demonstrating stable ammonia formation rates at low temperature. Additional acetylene pre-treatment leads to more dispersed active catalysts containing stable sub-nanometric Ru clusters.

Here we describe the formation of a trigonal prismatic cage, utilizing 2-formyl-1,8-naphthyridine subcomponents to bind pairs of silver(I) ions in close proximity. This cage is the first example of a new class of subcomponent self-assembled polyhedral structures having bimetallic vertices, as opposed to the single metal centers that typically serve as structural elements within such cages. Our new cage self-assembles around a pair of anionic templates, which are shown by crystallographic and solution-phase data to bind within the central cavity of the structure. Many different anions serve as competent templates and guests. Elongated dianions, such as the strong oxidizing agent peroxysulfate, also serve to template and bind within the cavity of the prism. The principle of using subcomponents that have more than one spatially close, but nonchelating, binding site may thus allow access to other higher-order structures with multimetallic vertices.

The cavities of artificial receptors are defined by how their components fit together. The encapsulation of specific molecules can thus be engineered by considering geometric principles; however, intermolecular interactions and steric fit scale with receptor size, such that the ability to bind multiple guests from a specific class of compounds remains a current challenge. By employing metal–organic self-assembly, we have prepared a triangular prism from two different ligands that is capable of binding more than 20 different natural products, drugs, and steroid derivatives within its prolate cavity. Encapsulation inflates the host, enhancing its ability to bind other guests in peripheral pockets and thus enabling our system to bind combinations of different drug and natural product cargoes in different locations simultaneously. This new mode of entropically favorable self-assembly thus enables central encapsulation to amplify guest-binding events around the periphery of an artificial receptor.

Obsidian provenance data plays a central role in reconstructions of patterns of interaction and trade in the North American Southwest. Unfortunately, there has been much less investment in obsidian provenance studies in the southern portion of this region, pertaining to Northwest Mexico, with the Sierra Madre Occidental and coastal regions of Sonora being acutely understudied. This study presents data on 338 specimens recovered in the former and offers a first glimpse of patterns from the late-precolonial era to historic period. We also report a characterization of one newly discovered source in this region, El Colorín de Jecota. Interpretations remain hampered by a significant number of “unknowns”. Patterns of obsidian transport contribute substantially to present interpretations that trade relationships were highly balkanized with communities evidencing variable levels of source diversity and procurement strategies that do not uniformly reflect a prioritization of spatial propinquity.

Still largely a unique process for steel founders, shrouded pouring trials showed a significant increase in metal cleanliness and a total cost savings. Over the years, the 'Clean Steel' projects [...]

I'll admit two things: I'm given to using analogies, and I enjoy a good bottle of wine. That leads me to ask why so many people who claim to know [...]

In March '99 I took a one-week tour of Sicily with Compagnia Siciliana Turismo, or CST (Via Amari 124, 90139 Palermo, Sicily; phone 091 582294, or fax 091 582218, or […]

Harrison Steel identified melting and pouring variables that affect melt cleanliness in an effort to establish procedures for the elimination of oxide macroinclusions. In 1995, Harrison Steel Castings Co., a [...]