Enhancement of Corn Nixtamalization by Power Ultrasound

Nixtamalization, a key production step for masa flour used for tacos, corn tortillas, and chips, traditionally involves corn kernel cooking for 1 h and a lengthy process of steeping (16–18 h) in a lime solution. This study aimed at accelerating the traditional nixtamalization (TN) process using power ultrasound with acoustic energy density around 1.85 W/g for 1 h during cooking followed by brief steeping for 1 h. The cooked kernels (nixtamal) were evaluated for texture and color, while the cooking liquor (nejayote) was evaluated for solid losses. The power ultrasound-assisted nixtamalization resulted in significantly (p?≤?0.05) reduced process time and softer nixtamal with less solid losses in nejayote than control (TN). Response surface methodology established significant relationships of sonication duration and cooking temperature to texture, color of nixtamal, and dry matter loss in nejayote. This study indicates that power ultrasound ameliorated traditional nixtamalization in terms of quality and operation time.     

Ten-year stability and latent structure of the DSM–IV schizotypal, borderline, avoidant, and obsessive-compulsive personality disorders.

Evaluation of the validity of personality disorder (PD) diagnostic constructs is important for the impending revision of the Diagnostic and Statistical Manual of Mental Disorders. Prior factor analytic studies have tested these constructs in cross-sectional studies, and models have been replicated longitudinally, but no study has tested a constrained longitudinal model. The authors examined 4 PDs in the Collaborative Longitudinal Personality Disorders study (schizotypal, borderline, avoidant, and obsessive-compulsive) over 7 time points (baseline, 6 months, 1 year, 2 years, 4 years, 6 years, and 10 years). Data for 2-, 4-, 6- and 10-year assessments were obtained in semistructured interviews by raters blind to prior PD diagnoses at each assessment. The latent structure of the 4 constructs was differentiated during the initial time points but became less differentiated over time as the mean levels of the constructs dropped and stability increased. Obsessive-compulsive PD became more correlated with schizotypal and borderline PD than with avoidant PD. The higher correlation among the constructs in later years may reflect greater shared base of pathology for chronic personality disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Geothermal power technology

In 1999, 8 GW_e of electrical generating plant worldwide was powered by geothermal heat. Geothermal sources generated 49 terawatt hours of virtually pollution-free power that year. Coal- or oil-fired plants generating this amount would discharge ~40 million tons per year of carbon dioxide into the atmosphere. Geothermal capacity has doubled in the past 20 years, and increased 17% in the past five years. The United States and the Philippines account for 50% of that installed capacity worldwide. The thermal energy stored in the upper 10 km of the Earth's crust is vast. For example, below the land surface of the US, it is estimated to be 10⁶ times annual energy demand for the country, but most of it is not economically accessible. The only thermal energy currently economic to extract is from sites where temperatures above 200°C are easily accessible by conventional drilling, and reservoirs of hot water or steam exist in the subsurface. To unlock a significant fraction of this vast energy source major technological advances are needed. These include improvements in drilling technology to lower the cost of wells, in fracture stimulation technology to create and control permeability in tight rocks, and in geophysical and chemical tracer technology to characterize thermal and hydraulic regimes in the subsurface. This will take a coordinated effort by government and industry over one or two decades     

A self-aligned elevated source/drain MOSFET

An advanced elevated source/drain CMOS process which features self-aligned lightly-doped drain (LDD) and channel implantation is described. Unlike conventional elevated source/drain structures which employ separate polysilicon deposition steps to define the source/drain and gate electrodes, this new structure provides self-alignment of the LDD regions with the heavily doped channel regions to avoid dopant compensation effects. This process employs a single selective silicon deposition step to define both the epitaxial source/drain and polycrystalline gate regions. A single sidewall spacer is used for both LDD and salicide definition. Unlike conventional elevated source/drain CMOS processes, the final MOSFET structure provides self-alignment of the LDD regions with the heavily doped channel regions. Salicidation is performed after selective silicon deposition to provide low sheet resistances for the source/drain and gate regions. Small-geometry NMOS and PMOS devices have been fabricated which display excellent short channel behavior     

Correlates of job satisfaction in naval environments.

Demographic, military status, job-related and health-related variables were correlated with a job satisfaction measure for 5,851 Navy enlisted men. Health-related variables were most highly correlated with satisfaction, followed by type of job and seniority. A multiple regression equation with 6 variables (symptom index, type of job, length of service, specific ship, number of men supervised, and worked closely with others) yielded a cross-validity coefficient of .49. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Treatment implications of past trauma in borderline personality disorder

Recent research and clinical experience have shown childhood trauma to be common in the histories of patients with borderline personality disorder. This article reviews the association between borderline personality disorder and early trauma, and how an awareness of the role of trauma may improve the treatment of patients with this disorder. Particularly when early trauma is in the form of childhood abuse, clinicians may be better able to understand the difficulties these patients experience in relational skills, affect tolerance, behavioral control, self-identity, and self-worth. Clinicians may be able to facilitate a stronger therapeutic alliance through acknowledgement of the patient's victimization and empathy with the effects of early trauma on the patient's life. Reframing the patient's experience as a consequence of childhood trauma is essential, especially when making traditional interventions such as interpretation and confrontation. The role of trauma in the development of borderline personality disorder suggests the need for modification of models of individual, family, and group psychotherapies that may allow more productive and successful treatment.     

The insect exoskeleton: A natural structural composite

Through untold centuries of evolutionary development, the insect exoskeleton has become a highly optimized structure suited to a variety of demanding duties. Microscopic examination of the bessbeetle cuticle indicates that it is a composite consisting of layered plies having fiber orientations that alternate in a dual helicoidal pattern. Further, the geometry and size of the reinforcing fibers varies with the position of the ply. Several interesting structures discovered in the insect exoskeleton may provide fodder for new ideas on composite joining, ply orientation and fiber size and geometry.     

A novel PMOS SOI polysilicon transistor

An advanced silicon-on-insulator (SOI) PMOS polysilicon transistor, featuring an inverted gate electrode and self-aligned source/drain and gate/channel regions, is developed and characterized. Selective oxidation is used to form self-aligned thin polysilicon channel regions with thicker source/drain polysilicon regions. The gate electrode is formed by a high-energy boron implant into the underlying silicon substrate. Since the gate oxide is formed over single-crystal silicon rather than polysilicon, an improvement in gate oxide integrity is possible. The resulting SOI PMOS device is suitable for high-density static random access memory (SRAM) circuit applications and exhibits excellent short-channel behavior with an on/off current ratio exceeding six orders of magnitude     

An advanced 0.5-μm CMOS disposable TiN LDD/salicide spacerprocess

An advanced 0.5-μm CMOS technology which features disposable TiN spacers to define both lightly doped drain (LDD) implantation and self-aligned silicided source, drain, and gate regions is discussed. Since the LDD implantation sequences are reversed using the disposable TiN spacers, this process results in CMOS devices with low salicided junction leakage, reduced source/drain lateral diffusion, and shallow phosphorus N^- and boron P^- regions for improved short-channel behavior