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The asterism observed in white radiation X-ray diffraction images (topographs) of extended cracks in silicon is investigated and found to be associated with material that is close to breakout and surrounded by extensive cracking. It is a measure of the mechanical damage occurring when the fracture planes do not follow the low-index cleavage planes associated with the crystal structure. It is not related to a propensity for some cracked wafers to shatter during subsequent high-temperature processing. There is no correlation between crack morphology and alignment of an indenter with respect to the orientation of a silicon wafer, the cracks being generated from the apices of the indenter and having threefold symmetry for Berkovich indents and fourfold symmetry for Vickers indents. X-ray diffraction imaging (XRDI) of indents does not reveal this underlying symmetry and the images exhibit a very substantial degree of variation in their extent. This arises because the XRDI contrast is sensitive to the long-range strain field around the indent and breakout reduces the extent of this long-range strain field. Breakout is also detected in the loss of symmetry in the short-range strain field imaged by scanning micro-Raman spectroscopy. Weak fourfold symmetric features at the extremes of the images, and lying along ⟨110⟩ directions, are discussed in the context of slip generated below the room-temperature indents. Scanning electron microscopy imaging of the region around an indent during focused ion beam milling has permitted the three-dimensional reconstruction of the crack morphology. The surface-breaking Palmqvist cracks are found to be directly connected to the median subsurface cracks, and the presence of extensive lateral cracks is a prerequisite for material breakout at indenter loads above 200 mN. The overall crack shape agrees with that predicted from simulation. [ABSTRACT FROM AUTHOR]

The apparatus for X-ray diffraction imaging (XRDI) of 450-mm wafers, is now placed at the ANKA synchrotron radiation source in Karlsruhe, is described in the context of the drive to inspect wafers for plastic deformation or mechanical damage. It is shown that full wafer maps at high resolution can be expected to take a few hours to record. However, we show from experiments on 200-, 300-, and 450-mm wafers that a perimeter-scan on a 450-mm wafer, to pick up edge damage and edge-originated slip sources, can be achieved in just over 10 min. Experiments at the Diamond Light Source, on wafers still in their cassettes, suggest that clean-room conditions may not be necessary for such characterization. We conclude that scaling up of the 300-mm format Jordan Valley tools, together with the existing facility at ANKA, provides satisfactory capability for future XRDI analysis of 450-mm wafers. [ABSTRACT FROM PUBLISHER]

To examine the impact of mechanical defects on the crystal lattice of silicon, controlled damage was applied to silicon wafers by a nanoindendation method. With increasing loads of 1, 5 and 50 N, the area with micro-cracks and strain around the indents increases. The damage is characterised by high resolution diffractometry using a conventional X-ray tube. Spatially resolved rocking curves were recorded across the indents and analysed with respect to full width at half maximum. From reciprocal space maps the amount of strain and tilt around the indents is separated. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The article discusses a study of the thermal slip sources (TSS) at the extremity and bevel edge of a silicon wafer (SW). The authors performed rapid thermal annealing (RTA) on a 200-millimeter SW, which showed no edge defects either under optical inspection or X-ray diffraction imaging. They found that the dislocation velocity is constant during slip-band nucleation. They also observed that the majority of TSS appear at the extremity of the SW and are not suppressed by the RTA apparatus.

We report the first observation of sclerosteosis in Spain. To the best of our knowledge, this is the first case of sclerosteosis in a person of Mediterranean origin with no known Dutch ancestors. He has the characteristic phenotype of the disease with right facial nerve palsy and syndactyly and the typical radiological features, including generalised bone sclerosis and cortical widening of the tubular bones. [ABSTRACT FROM PUBLISHER]

A correction to the article "Shifts in clostridia, bacteroides and immunoglobulin-coating fecal bacteria associated with weight loss in obese adolescents," by I. Nadal and colleagues that was published in the 2012 issue is presented.

We show that x-ray diffraction imaging (topography) and finite-element modelling can determine accurately the probability of propagation of individual cracks in brittle single crystal materials. The x-ray image of the crack provides a critical parameter for crack propagation which informs a predictive model, enabling us to identify critical defects that lead to catastrophic shattering of silicon wafers during high temperature thermal processing. Wafers fracture on cooling and finite element modelling shows that, during cooling, the tangential stress at the wafer edge is tensile and results in crack propagation. The predicted fracture geometry agrees extremely well with that observed experimentally. [ABSTRACT FROM AUTHOR]

Abstract: In the semiconductor manufacturing industry, wafer handling introduces micro-cracks at the wafer edge. During heat treatment these can produce larger, long range cracks in the wafer which can cause wafer breakage during manufacture. Two complimentary techniques, micro-Raman spectroscopy (μRS) and White Beam Synchrotron X-ray Topography (WBSXRT) were employed to study both the micro-cracks and the associated strain fields produced by nano-indentations in Si wafers, which were used as a means of introducing controlled strain in the wafers. It is shown that both the spatial lateral and depth distribution of these long range strain fields are relatively isotropic in nature. The Raman spectra suggest the presence of a region under tensile strain beneath the indents, which can indicate a crack beneath the indent and the data strongly suggests that there exists a minimum critical applied load below which cracking will not initiate. [Copyright &y& Elsevier]

The behaviour of microcracks in silicon during thermal annealing has been studied using in situ X-ray diffraction imaging. Initial cracks are produced with an indenter at the edge of a conventional Si wafer, which was heated under temperature gradients to produce thermal stress. At temperatures where Si is still in the brittle regime, the strain may accumulate if a microcrack is pinned. If a critical value is exceeded either a new or a longer crack will be formed, which results with high probability in wafer breakage. The strain reduces most efficiently by forming ( hhl ) or ( hkl ) crack planes of high energy instead of the expected low-energy cleavage planes like {111}. Dangerous cracks, which become active during heat treatment and may shatter the whole wafer, can be identified from diffraction images simply by measuring the geometrical dimensions of the strain-related contrast around the crack tip. Once the plastic regime at higher temperature is reached, strain is reduced by generating dislocation loops and slip bands and no wafer breakage occurs. There is only a small temperature window within which crack propagation is possible during rapid annealing.

Objective: To evaluate the effects of a multidisciplinary obesity treatment programme on fecal microbiota composition and immunoglobulin-coating bacteria in overweight and obese adolescents and their relationship to weight loss., Design: Longitudinal intervention study based on both a calorie-restricted diet (calorie reduction=10-40%) and increased physical activity (calorie expenditure=15-23 kcal/kg body weight per week) for 10 weeks., Participants: Thirty-nine overweight and obese adolescents (BMI mean 33.1 range 23.7-50.4; age mean 14.8 range, 13.0-16.0)., Measurements: BMI, BMI z-scores and plasma biochemical parameters were measured before and after the intervention. Fecal microbiota was analyzed by fluorescent in situ hybridization. Immunoglobulin-coating bacteria were detected using fluorescent-labelled F(ab')2 antihuman IgA, IgG and IgM., Results: Reductions in Clostridium histolyticum and E. rectale-C. coccoides proportions significantly correlated with weight and BMI z-score reductions in the whole adolescent population. Proportions of C. histolyticum, C. lituseburense and E. rectale-C. coccoides dropped significantly whereas those of the Bacteroides-Prevotella group increased after the intervention in those adolescents who lost more than 4 kg. Total fecal energy was almost significantly reduced in the same group of adolescents but not in the group that lost less than 2.5 kg. IgA-coating bacterial proportions also decreased significantly in participants who lost more than 6 kg after the intervention, paralleled to reductions in C. histolyticum and E. rectale-C. coccoides populations. E. rectale-C. coccoides proportions also correlated with weight loss and BMI z-score reduction in participants whose weight loss exceeded 4 kg., Conclusions: Specific gut bacteria and an associated IgA response were related to body weight changes in adolescents under lifestyle intervention. These results suggest interactions between diet, gut microbiota and host metabolism and immunity in obesity.

Introduction: The number of patients with glucose tolerance alterations associated with cystic fibrosis (CF) has increased, probably due to the greater survival rate among sufferers of this disease. We studied impaired glucose tolerance (IGT) in patients with CF and investigated whether its appearance has any relationship with age, sex, genetic mutation and/or the degree of clinical involvement. We assessed the parameters that might allow early detection., Patients and Methods: In 28 patients with CF (14 M, 14 F; aged 22 months to 18 years), sex, genetic mutation, nutritional status and the degree of pancreatic and pulmonary involvement were recorded. The metabolic study included glycosylated hemoglobin (HbA1c) determination, oral glucose tolerance test (OGTT) and intravenous glucose tolerance tests (IVGTT)., Results: In the patients with CF, 35.71% showed impaired glucose tolerance (IGT) and 3.57% had diabetes mellitus. The patients with IGT and CF were 3.2 years older than those with normal glucose tolerance (NGT; p<0.05), but no significant differences were found regarding sex, anthropometric measurements, percentage of pulmonary gammagraphic involvement, Shwachman-Kulczycki test or HbA1c. In the OGTT, the patients homozygous for the deltaF508 mutation had higher blood glucose values than the heterozygous group (p=0.03), but these values were not higher than those in patients with other mutations. During the OGTT, blood insulin values at 30' were reduced in patients with IGT compared to patients with NGT (p<0.02) and the insulin peak occurred at 100.9+/-24.3 min compared to 65.3+/-21.8, respectively (p<0.05). In the IVGTT, 82.14% of the patients had reduced insulin levels at 1 and 3 min (I1'+3'). No differences in the blood glucose levels during the OGTT were found between patients with normal I1'+3' values and patients with reduced values., Conclusions: A high percentage of patients with CF also present with IGT. This increases with age and is more common among patients homozygous for the deltaF508 mutation and is not related to clinical status. Alterations in the kinetics of insulin secretion play an important role in the appearance of IGT and CF. We suggest that the OGTT is a more sensitive method than IVGTT for identifying early alterations in CF-related diabetes mellitus.

More than 80% of children with growth hormone deficiency (GHD) respond with a rise in growth hormone levels when given 1 microgram/kg body weight of growth hormone-releasing hormone (GHRH) in an i.v. bolus. We conducted a study to determine whether the failure of the remaining 20% to respond to GHRH is due to a pituitary deficiency or a secondary effect associated with chronically understimulated somatotrophs. We administered GHRH to "prime" 16 short-statured children (> 2 SD) presenting delayed growth (< 4 cm/year), who had not responded initially when given a single dose of GHRH. Priming consisted of administering GHRH (1-29) NH2 (5 micrograms/kg body weight, s.c.) for six consecutive days. Plasma GH response was studied again after an i.v. injection of 1 microgram/kg body weight of GHRH (1-29) NH2 on the seventh morning. On the basis of these results we were able to separate our patients into two groups: a) responders to priming (n = 8), whose GH responses to pharmacological and acute GHRH tests were < 10 ng/ml, with a 12-hour sleep secretion < 3 ng/ml/min. Priming increased the plasma GH response to acute GHRH in all the children in this group (6.0 +/- 2.1 ng/ml to 18.0 +/- 5.4 ng/ml; p < 0.001); b) non-responders to priming (n = 8), whose GH responses to pharmacological and acute GHRH tests were also < 10 ng/ml, with 12-hour sleep secretion < 3 ng/ml/min, but in whom priming with GH did not increase the plasma GH response (5.5 +/- 2.8 ng/ml to 6.2 +/- 2.9 ng/ml; p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)

6 girls, aged 4-16 years, with acanthosis nigricans and hirsutism were studied. Fasting and postglucose hyperinsulinism was present in the 5 older girls. In the youngest, a transitory diabetes with hyperinsulinism was induced by a cortisone therapy for hepatitis. Insulin resistance, suggested by the failure to significantly decrease blood glucose after insulin injection (0.1 U/kg), was demonstrated in three steps: (1) Patient plasma failed to bind 125I-insulin after a 5-day incubation followed by precipitation by antihuman globulin serum. (2) Specific 125I-insulin binding to rat liver membranes was identical in the presence of patient plasma and control plasma. (3) Specific 125I-insulin binding to the erythrocytes of the 6 patients (3.5-7.0%) was significantly lower (p less than 0.01) than in controls (4.5-19.5%). Moreover, the significant correlation present in controls between total binding and reticulocyte counts (r = 0.824, p less than 0.001) was absent in the patients. These data demonstrate further that, in the juvenile type of acanthosis nigricans, insulin resistance which may precede hyperinsulinism is not related to anti-insulin antibodies nor to antireceptor antibodies, but results from a primary defect of insulin receptors.

The case of a 12 2/12-year-old boy with an HGH secreting eosinophilic adenoma is presented. The histologic investigation included conventional and ultrastructural techniques. The pre- and postoperative (1, 7, 11, and 20 months) hormonal controls are analyzed, indicating the persistence of HGH anteropituitary activity, even though surgical sectioning of the pituitary stalk was performed and the activities of thyroid, corticoadrenal and gonadotropin functions decreased. It is suggested that the hypothalamo-pituitary relationship may be maintained by extraportal venous circulations.

One hundred and fifty-three children with common cryptorchidism, 109 unilateral and 44 bilateral, excluding those with associated malformations or abnormalities, were treated at age 6 to 59 months with human chorionic gonadotropin given as nine intramuscular injections on alternate days. Treatment before age 3 years resulted in complete failure in 81%. At 3 to 4 years of age treatment resulted in failure in 55%, but 19% of the patients showed complete testicular descent and 26% showed partial descent. The percent of failures was increased when the dose of human chorionic gonadotropin was lower than 1,000 IU/m2 injection and when the cryptorchid testis was very high. No correlation was found between endocrine data and the clinical results. The plasma testosterone concentration after the third injection of human chorionic gonadotropin was not significantly different in successfully and unsuccessfully treated patients. However, testosterone levels were significantly lower in patients treated at 36 to 59 months of age than in those treated at an earlier age, in contrast to the significantly better clinical results obtained in the older group. Thus human chorionic gonadotropin is not a valuable means of obtaining descent of undescended testes before age 3 years and is of limited usefulness at age 3 to 4 years.

The purpose of this study is to assess the relative effects of body fat distribution and obesity "per se" on serum glucose, insulin, and insulin resistance. Seventeen obese and nine nonobese control prepubertal girls were studied. Biceps, triceps, subscapular, and suprailiac skinfold thickness were measured. Percentage of body fat (% BF) and total body fat (TBF) were calculated. Body fat distribution was assessed by analyzing the central (suprailiac, subscapular)/peripheral (biceps, triceps) ratios. Oral glucose tolerance test was performed. Serum glucose and insulin were measured and insulinogenic index (insulin/glucose) was calculated. Body fat anthropometric data and body fat distribution indexes were significantly higher (p less than 0.001) in the obese group. The obese population presented significantly elevated values of glucose, insulin, and insulinogenic indexes (p less than 0.01-p less than 0.001). In the obese group, insulin showed significant positive correlations (p less than 0.05-p less than 0.001) with biceps, subscapular, and suprailiac skinfolds, % BF and TBF, whereas the insulinogenic index had positive correlations with suprailiac skinfold and TBF (p less than 0.05). Obese girls showed positive correlations between the body fat distribution indexes and insulin or insulinogenic indexes (p less than 0.05-p less than 0.001). In prepubertal girls obesity is of the centripetal (central) type. This pattern has an important role in determining the alterations in the glucose-insulin homeostasis that characterize the childhood nutritional obesity.