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I carry out numerical scattering calculations against a family of finite-length one-dimensional point-like arrangements of atoms, $\chi(x)$, related to the distribution of prime numbers by a shift operation making the atomic density approximately constant. I show how the Riemann Zeta Function (RZF) naturally parameterizes the analytic structure of the scattering amplitude and give numerical results.

We have coupled electron microscopy and energy dispersive spectroscopy experiments with \textit{ab-initio} modeling to study the solubility and diffusion of Au in Bi$_2$Te$_3$. We found that thermal annealing of Au films results in Au concentrations in Bi$_2$Te$_3$ above the previously reported solubility limit. The time scale of Au diffusion into Bi$_2$Te$_3$ is also much greater than expected. To explain our observations, we calculate defect formation energies and diffusion barriers within DFT. We identify an interstitial mechanism consistent with the previously observed low solubility and (rapid) anisotropic diffusion. However, the lower formation energies of substitutional defects suggest that they may be active in our experiments and explain the high observed concentrations., Comment: Version 2

Electronic and optoelectronic devices based on thin films of carbon nanotubes are currently limited by the presence of metallic nanotubes. Here we present a novel approach based on nanotube alkyl functionalization to physically remove the metallic nanotubes from such network devices. The process relies on preferential thermal desorption of the alkyls from the semiconducting nanotubes and the subsequent dissolution and selective removal of the metallic nanotubes in chloroform. The approach is versatile and is applied to devices post-fabrication.

We search for new fully compensated half metals, in which only one electronic spin channel is conducting and there exists no net magnetic moment. We focus on half Heusler alloys and we examine the physical consequence of different crystal structures found in the literature for these compounds, XMnZ, with a transition metal element, such as Cr, Mn, and Fe for X and a nonmetallic element, such as P, Sb and Si for Z. The structures differ in the placement of voids in the L2$_1$ structure of the full Heulser alloy. One structure has the void at (1/4, 3/4, 1/4)a and the other places the void at (0.0, 0.0, 1/2)a. The first structure is expected to have greater d-p hybridization between Mn and the Z atom. The other exhibits strong d-d hybridization between the nearest neighboring transition metal elements. Five XMnZ compounds are considered along with the previously studied CrMnSb in the second structure, which serves as a reference. Besides the CrMnSb, only one other alloy, MnMnSi, shows fully compensated half metallic properties in both structures. Both these alloys obey the Slater-Pauling electron counting rule for half Hesuler alloys. The differences between CrMnSb and MnMnSi in the two structures are discussed based on their atomic properties. In the search for fully compensated half metals in transition metal-based half Heusler alloys, we suggest using the counting rule as a guide., Comment: 9 figures, 7 pages

Single dopings of Mn and Fe in Si are investigated using 8-, 64-, and 216-atom supercells and a first-principles method based on density functional theory. Between the two transition metal elements (TMEs), atom sizes play an essential role in determining the contraction or the expansion of neighboring atoms around the TME dopant at a substitutional site. At a tetrahedral interstitial site, there is only expansion. Magnetic moments/TME at the two sites are calculated. Physical origins for these inter-related properties are discussed. A few suggestions about the growth of these Si-based alloys are given., Comment: 5 figures

Recently, the magnetic moment/Mn, $M$, in Mn$_x$Si$_{1-x}$ was measured to be 5.0 $\mu_B$/Mn, at $x$ =0.1%. To understand this observed $M$, we investigate several Mn$_x$Si$_{1-x}$ models of alloys using first-principles density functional methods. The only model giving $M = 5.0$ was a 513-atom cell having the Mn at a substitutional site, and Si at a second-neighbor interstitial site. The observed large moment is a consequence of the weakened d-p hybridization between the Mn and one of its nearest neighbor Si atoms, resulting from the introduction of the second-neighbor interstitial Si. Our result suggests a way to tune the magnetic moments of transition metal doped semiconductors., Comment: 4 pages, 2 figures

Students are socialized into a subculture of education through many means, but many students encounter only the lecture method, especially in the general education curriculum. The lecture approach is commonly associated with multiple choice testing, and some students may go through college without taking, or learning to take, other kinds of tests. Many colleges adhere to the lecture/take notes/take tests model. For some students, there are competency based classes that adhere to skill based models. Rather than earning a grade through multiple choice tests, the student is forced to perform. This is especially evident for education students who must student teach. Evaluations are based on the subjective evaluation of the instructor. Some students are not able to make the transition to the performance based approach. However, in the future, teachers will increasingly be faced with the demand to provide instruction and knowledge to students in an increasingly computerized, sophisticated, electronic fashion. Students must be socialized anew to accept feedback and evaluations that are of more than multiple choice nature. (SLD)

This article discusses the impact of instructional television, directed study courses, and other alternative teacher certification methods. Colleges and universities are becoming aware of nontraditional programs that require minimal, if any, time on campus or direct contact with instructors. Soon, there will be a proliferation of Internet courses. This trend may result in: teachers who are proficient in procuring the most credit hours with the least work; teachers with significant theoretical knowledge but no interpersonal skills; and people who lack the college experience. Research shows that: in times of high competition for teaching jobs, most teachers are traditionally certified; in times of high demand for new teachers, significant numbers of new teachers are either alternatively certified, given emergency certification, or uncertified; alternatively certified teachers are less qualified than traditionally certified teachers; and better qualified teachers produce better qualified students. There is a concern that special educators are not receiving sufficient training to handle their students' special needs and that regular educators do not have the skills to teach mainstreamed students. The paper cautions that people may begin to question the skills of teachers who have taken mainly correspondence and web based courses to fulfill their degree requirements. (SM)

The improvement of college students' reading rate and comprehension is a major educational concern. Many students arrive at college unprepared for the massive amount of required reading. This study presents several attempts to improve vocabulary, reading rate, and comprehension and addresses tangential issues related to the improvement of reading at the college level. Students were asked to indicate the number of credit hours taken, hours worked outside of school, and number of children in the home. These were used as co-variates to examine their influence on reading rate, comprehension, and vocabulary. The results are examined within an information processing context. (RS)

Mentoring individuals who are gifted, talented, and creative, but somewhat emotionally sensitive is a challenging and provocative arena. Several reasons individuals experience heightened sensitivity include: lack of nurturing, abuse, alcoholism in the family, low self-esteem, unrealistic parental expectations, and parental pressure to achieve. Alexithymia is defined as a condition in which children do not seem to experience emotions, or the emotions are expressed through physical symptoms (i.e., ulcers, high blood pressure, and headaches). How this condition effects individuals in adulthood is described. Individual differences in sensitivity to feedback may result from learned differences in mental models of the self. This affects the ways in which individuals function. The paper discusses several defensive behaviors of emotionally sensitive individuals and explains how mentors can best respond to them. Eleven specific suggestions for mentors working with this population are provided. Coping skills that mentors can teach to emotionally sensitive people are listed. (MKA)

This paper provides a list of signs, symptoms, and indicators of emotionally sensitive adolescents includes clinging behavior, withdrawn behavior, shy/inhibited behavior, represses anger, poor reaction to criticism, makes self-disparaging statements, low self-esteem, "can't forgive self or others," ruined by a small critical comment, exploding when criticized, emotionally volatile, and depression. Causes reviewed include dysfunctional families, divorce, unrealistic expectations, abuse or neglect, and parenting "enmeshment." Gifted children often seem to be more emotionally sensitive than other children. Teaching, parenting, and counseling issues that must be examined as possible contributors to the problem include standards, especially inordinately high standards; past reinforcement history, and the vagaries of parenting response due to divorce. The emotionally sensitive adolescent has many concerns including teachers' expectations, comparison to siblings, feelings of inferiority, inadequacy or rejection, divorce, moving, and bullies. Parental guidelines are presented; music and art therapy are recommended. Prognosis is discussed. (EMK)

This paper presents the preliminary results of a longitudinal study to assess the development of critical thinking as preservice teachers progress through their educational program. Students will be assessed during their final year in the program to help give an overview of the growth of their critical thinking skills. The Cornell Critical Thinking Test (Level Z) was administered to students in elementary (n=44), secondary (n=20), political science (n=24), psychology (n=19), and a combined group of early childhood, bilingual, and special education students (n=11). Those enrolled in the student teacher program will be assessed again to evaluate their growth in thinking skills. The means and standard deviations for the groups are presented in tables, with means similar across the groups. Study results indicated that few teachers, programs, and institutions actively integrate, assess, teach, and evaluate critical thinking across the curriculum. Further, while teachers are expected to teach critical thinking skills, teachers are rarely taught specifically how to teach these skills. (ND)

A 1997 survey examined the stress factors and perceived remedies of 45 K-12 student teachers and 40 K-12 cooperating teachers. Stressful events they listed included material selection, unmotivated students, working with peers, supervisor's visits, discipline, preparing for the unexpected, relationships with parents, cooperating teachers, lecture, inconsistent student behavior, time management, power debates with students, and relationships with students. Perceived solutions included expelling disruptive students, inservice workshops, parent involvement, increased security, class size reduction, payment for student teaching, presence or absence of cooperating teacher from the classroom, reduction of interruptions from pull-out programs, reduction or increase in visits by college supervisors, and having full control of the classroom from the beginning to the end of student teaching. Teachers in this survey appeared to prefer more input into the removal of students with disciplinary problems over more computers and supplies, merit pay, or better benefits. One conclusion is that teachers need better preparation for dealing with diverse students and their various needs and with disruptive, unmotivated students. (SM)

This paper reviews the literature and offers an international perspective on current programs and issues in training individuals with mental retardation to parent, nurture, and care for their children. The first section reviews the limited research on the development of children of mothers with mental retardation, some existing parent training programs, and outcomes in parenting education for these parents. The second section specifically addresses parenting and sexuality education for parents with mental retardation. Some guidelines for parents are offered. A section on international perspectives describes a Canadian parenting education program for this population. Parenting education efforts in Australia, Pakistan, Finland, and Korea are briefly reviewed. The procedure used in Hong Kong to assess an individual's ability to understand and consent to the responsibilities of marriage is explained. The paper urges more systematic and standardized research in this area. (Contains 38 references.) (DB)

As concern about the developmental progress of preschoolers has increased, the number of assessment instruments available has expanded. This paper reviews recent advances in early childhood assessment and evaluation, and describes several screening and assessment instruments. Varying information is presented for each test, but may include a description, its applications, available training materials, and information on reliability and validity. Screening tests include: (1) "Developmental Indicators for the Assessment of Learning-Revised"; (2) "Early Screening Profiles"; (3) "FirstSTEP: Screening Test for Evaluating Preschoolers"; and (4) "Kaufman Survey of Early Academic and Language Skills." Seven language tests are described, including: (1) "Oral and Written Language Scales"; and (2) "Test de Vocabulario en Imagenes Peabody" (Spanish version of "Peabody Picture Vocabulary Test"). Nine intellectual screening and assessment instruments are described, including: (1) "Kaufman Brief Intelligence Test"; (2) "Mullen Scales of Early Learning"; (3) "Infant-Toddler Developmental Assessment"; (4) "Bayley Scales of Infant Development"; (5) "Wechsler Preschool and Primary Scale of Intelligence-Revised"; and (6) "Kaufman Assessment Battery for Children." Also described is a parent instrument, "Child Development Inventory"; "System to Plan Early Childhood Services"; "Test of Variables of Attention"; and "Behavior Assessment System for Children." The descriptions note which tests have Spanish directions and which are especially appropriate for children with language delays, and briefly describes several resources available on early childhood assessment. (Contains 11 references.) (KDFB)

Developments in the measurement and theory of creativity are reviewed, and the present status of creativity vis-a-vis psychometrics and theory is explored. The realm of creativity has been a quagmire of definition problems, with creativity variously defined in terms of process or stages. In past eras, creativity was essentially measured by output or productivity. Contemporary measures include the Torrance tests, derived from the structure of intellect model, and various tests such as the Remote Associates Test (Mednick, 1962), the Starkweather Originality Test (1974), the Group Inventory for Finding Creative Talent (1980), the Barron Welsh Art Scale, and a number of rating scales and surveys. The proliferation of tests suggests that it is necessary to review the components of a test before issuing it, looking for an operational definition of creativity and support for test reliability and validity. Minimum requirements include: (1) outside empirical support for the test; (2) long-term follow-up studies; (3) comparison measures against other recognized measures; (4) essential basic agreement in the field as to what "creativity" means; and (5) an adequate theoretical base for research and test construction. (Contains 36 references.) (SLD)