Lower GA Research Articles

Transcriptomes of Fruit Cavity Revealed by De Novo Sequence Analysis in Nai Plum (Prunus salicina)

Nai plum (Prunus salicina) is an important fruit crop in China having good taste and flavour. Cavity formation occurring during fruit development affects fruit quality. However, the molecular mechanism underlying cavity formation is unclear. To obtain differential expression profiles of cavity fruit (CF) and non-cavity fruit (nCF) in P. salicina, we sequenced the fruits at different time intervals of 7 days after anthesis (DAA), 21 and 28 DAA, respectively, and 83,869 unigenes, 3811 differentially expressed genes, 22,971 simple sequence repeats and over 14,000 single nucleotide polymorphisms were obtained. Twenty-three differentially expressed genes were selected for verification by qRT-PCR. The contents of phytohormones during fruit development showed that there was a positive relevance between phytohormone contents (IAA, ZR and GA), fruit size and ABA contents in the fruits, whereas there was a negative correlation with ZR, GA and IAA. Lower GA content in fruit before 14 DAA and higher IAA and ZR levels during later developmental stages resulted in cavity appearance. Further studies showed that differential expression of phytohormone-related genes IPT, CKX, YUCCA, GA20ox, GID1, CCS1 was determined at key fruit development stages, which is consistent with content changes of IAA, GA, ABA and ZR. Our results suggest that ABA might inhibit the synthesis of IAA, ZR and GA and cause fruit cavity formation in Nai plum.

Incidence and outcomes of acute kidney injury in extremely-low-birth-weight infants.

BackgroundAcute kidney injury (AKI) is a common event in the neonatal intensive care unit (NICU), especially in extremely-low-birth-weight (ELBW) infants. This cohort study investigated the incidence of and risk factors for AKI in ELBW infants and their overall survival at the postmenstrual age (PMA) of 36 weeks.MethodsAll ELBW infants admitted to our NICU between January 2010 and December 2013 were enrolled. Those who died prior to 72 hours of life, had congenital renal abnormality, or had only one datum of the serum creatinine (SCr) level after the first 24 hours of life were excluded. The criteria used for the diagnosis of AKI was set according to the modified neonatal KDIGO AKI definition.ResultsAKI occurred in 56% of 276 infants. Specifically, stage 1, stage 2, and stage 3 AKI occurred in 30%, 17%, and 9% of ELBW infants, respectively. High-frequency ventilation support (adjusted odds ratio [OR]: 3.4, 95% confidence interval [CI]: 1.78–6.67, p< 0.001), the presence of patent ductus arteriosus (adjusted OR: 4.3, 95% CI: 2.25–8.07, p < 0.001), lower gestational age (adjusted OR for gestational age: 0.7, 95% CI: 0.58–0.83, < 0.001), and inotropic agent use (adjusted OR: 2.6, 95% CI: 1.31–5.21, p = 0.006) were independently associated with AKI. Maternal pre-eclampsia was a protective factor (adjusted OR: 0.4, 95% CI: 0.14–0.97, p = 0.044). Infants with AKI had higher mortality before the PMA of 36 weeks with an adjusted hazard ratio (HR) of 5.34 (95% CI: 1.21–23.53, p = 0.027). Additionally, infants with stage 3 AKI had a highest HR of 10.60, 95% CI: 2.09–53.67, p = 0.004).ConclusionAKI was a very common event (56%) in ELBW infants and was associated with a lower GA, high-frequency ventilation support, the presence of PDA, and inotropic agent use. AKI reduced survival of ELBW infants before the PMA of 36 weeks.

Mueilha rare metals granite, Eastern Desert of Egypt: An example of a magmatic-hydrothermal system in the Arabian-Nubian Shield

The Mueilha granite pluton is one of the rare-metals bearing peraluminous granitic plutons in the Arabian-Nubian Shield. It represents the apical part of a highly evolved magma chamber emplaced at a shallow level subsequent to the post Pan-African orogeny. The pluton can be seen as a highly leucocratic medium-grained albite/oligoclase framework infilled with quartz, K-feldspar and muscovite that are variably overgrown by K-feldspar, muscovite, quartz and topaz megacrysts. The increasing number and size of the K-feldspar megacrysts at the expense of the whitened albite/oligoclase framework imparts variably red color to the Mueilha granite. Contacts between the milky white and red granites are usually gradational, but may be locally sharp or may form narrow transition zones resulting from abrupt variations in texture and lithology. Textural relations indicate an initial stage of hydrothermal albitization of magmatic plagioclase and crystallization of topaz megacrysts resulting from infiltration of Na-rich fluorine bearing fluids. A subsequent stage of metasomatic enrichment is characterized by extensive growth of large K-feldspar, quartz and muscovite megacrysts at the expense of the albite/oligoclase crystals as a result of infiltration of K-Si rich hydrous fluids. Post-magmatic infiltration of hydrous fluids along the fault planes is shown by the intense replacement of alkali feldspar megacrysts by quartz, development of myrmekitic intergrowth pockets along the K-feldspar megacrysts and sealing of the micro-fractures by cryptocrystalline mixtures of clay minerals, iron oxides, sericite and chlorite. Compositionally, the red granitic rocks have higher SiO2, Fe2O3total, K2O/Na2O, Σ REE, Y, Th, U, Zr and Zn and lower Al2O3, Ga, Ta, Nb and Mo compared to the milky white granites. LILE and Sn do not show clear variation trends throughout the Mueilha granite pluton, suggesting their immobility during hydrothermal alteration. Microthermometric measurements indicate that the interactions with the hydrothermal fluids started at a minimum temperature >400°C, most likely during the late-stage crystallization of the Mueilha granite and continued after their complete solidification (i.e. subsolidus conditions) at a temperature as low as 120°C. The high fertility of Mueilha granite is most plausibly the result of partial melting within the undepleted juvenile crust of the Arabian–Nubian Shield that has formed during the Pan-African orogeny.

Maternal Serum Amyloid A Level in Pregnancies Complicated with Preterm Premature Rupture of Membranes

Background: serum amyloid A (SAA) is a cytokine-inducible acute-phase reactant whose plasma concentrations can exceed 1 mg/mL during an acute-phase response (500 to 1000 fold of plasma levels greater than in the non inflammatory state) thus representing an ideal marker for clinical use. Preterm premature rupture of membranes (PPROM) complicates only 2% of pregnancies but is associated with 40% of preterm deliveries and can result in significant neonatal morbidity (Prematurity, sepsis and pulmonary hypoplasia) and mortality. Aim of the work: this study aimed to find out association between maternal serum amyloid A level and preterm premature rupture of membranes. Also to compare SAA, CRP levels, N/L ratio in the study group. Patients and methods: this study is a cross sectional study conducted in Ain Shams University Maternity Hospital from December 2015 – December 2016 on 58 pregnant women. Women have been allocated in this study, represented in two groups: 1- Study group: including 29 women complaining of preterm premature rupture of membranes. 2- Control group: including 29 women as control group with no complain. Venous blood sample was taken from each participant (study group within 1hour from onset of PPROM, control group during their follow up visit to the clinics). Serum amyloid A, Micro C reactive pretein, total WBCs and neutrophil/lymphocyte ratio (NLR) were calculated. Results: the results point out that PPROM cases had significantly lower GA and APGAR scores at 1 min and more prone to neonatal sepsis which may lead to death. PPROM women have significantly higher total WBC, N/L ratio CRP and serum amyloid A. There were significant positive correlations between amyloid-A, N/L ratio& CRP in both groups. Serum amyloid A level above 2 ng/ml is a risk factor for PPROM and low Apgar score at 1 min. but has low predictive value. CRP with cut off value 5.0 mg/dl has better predictive value in discrimination between PPROM group and control group.Conclusion: Results assessed possible association between maternal SAA, maternal and fetal parameters in pregnancies complicated with PPROM.

Development of a novel bioactive glass suitable for osteosarcoma-related bone grafts.

In this study, zinc borate-based glasses with increasing gallium content (0, 2.5, 5, 10, and 15 wt % Ga) were synthesized and their effect on the viability and proliferation of preosteoblasts and osteosarcoma cancer cells were investigated. Methyl thiazolyl tetrazolium (MTT) cell viability assays using glass degradation extracts revealed that the extracts from glasses with lower Ga contents could enhance the viability of preosteoblasts, while extracts from the glass composition with 15 wt% Ga caused statistically significant reduction of their viability. MTT cell viability assays using the extracts and osteosarcoma cells showed that only extracts from the glass composition with 5 wt% Ga (G3) did not cause a statistically significant increase in the viability of cancer cells for all degradation periods (1 day, 7 days, and 28 days). G3 was selected as the most suitable composition for the osteosarcoma-related graft operations as it could improve the viability of preosteoblasts without increasing the viability of cancer cells. The viability of preosteoblasts and osteosarcoma cells in contact with the glass powders were also investigated using MTT assays. The results showed that the G3 powders could enhance the viability of preosteoblasts while decreasing the viability of osteosarcoma cells. Finally, live/dead assays revealed that suppression of proliferation appeared to be the mechanism causing the observed reductions in the viability of osteosarcoma cells exposed to G3 powders. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1186-1193, 2018.

Comparative analysis and the coverage intervals of hair rare metal content in two Russian industrial centres

ABSTRACTThe existing data provide information on hair essential and toxic trace element content, whereas data on ultra-trace and rare elements are scarce. Therefore, the primary aim of the current study was to estimate hair levels and reference values of hair rare metal content using IUPAC recommendations in 2593 occupationally non-exposed adults living in Moscow and Novosibirsk (1900 women and 693 men). Hair Ag, Au, Ga, Ge, La, Rb, Tl, W and Zr content was assessed by inductively coupled plasma mass spectrometry with NexION 300D. Women were characterised by significantly higher hair Ag and Au levels than men, whereas men had increased La, Rb, Tl, W and Zr content as compared to women. Moscow inhabitants were characterised by significantly higher hair Au and Ge, and lower hair Ga, La, Rb, Tl, W and Zr content as compared to the ones from Novosibirsk. The coverage intervals of Ag, Au, Ga, Ge, La, Rb, Tl, W and Zr content in hair of the general sample of examinees calculated in accordance with IUPAC recommendations were 0.0278–0.2994, 0.0159–0.1812, 0.0062–0.0348, 0.0022–0.0066, 0.0023–0.0205, 0.0226–0.2083, 0.0002–0.0008, 0.0022–0.0120 and 0.0389–0.3521 μg/g, respectively. The obtained data indicate that both gender and geographical location affect hair rare metal content in adults.

The Nature of the Isolated Gallium Active Center for Propane Dehydrogenation on Ga/SiO2

Single-site Ga/SiO2 catalysts exhibit up to 99% C3H6 selectivity at 4% propane conversion with an initial rate of 5.4 × 10−4 (mole C3H6) (mole Ga)−1 s−1 during propane dehydrogenation (PDH) at 550 °C. Following pre-treatment in H2 at 550 °C, only four-coordinate, Ga3+–O Lewis acid sites are observed under reaction conditions. At 650 °C in H2, an additional isolated Ga site with lower Ga–O coordination (N Ga−O < 4) is formed and leads to a 30% decrease in the initial PDH rate per total moles of Ga. The PDH rates are equivalent when normalized by the amount of surface, four-coordinate Ga3+–O, regardless of catalyst pre-treatment conditions, which indicates that these isolated Ga3+ centers are the catalytically relevant sites. Isolated, Lewis acidic Ga3+ cations present as four-coordinate Ga3+–O centers exhibit up to 99% C3H6 selectivity during propane dehydrogenation (PDH) at 550 °C. An additional isolated Ga site with lower Ga–O coordination is formed during H2 treatment at elevated temperatures, but is inactive for PDH and reversibly decomposes under reaction conditions.

Gallium-Doped Li7La3Zr2O12 Garnet-Type Electrolytes with High Lithium-Ion Conductivity.

Owing to their high conductivity, crystalline Li7-3xGaxLa3Zr2O12 garnets are promising electrolytes for all-solid-state lithium-ion batteries. Herein, the influence of Ga doping on the phase, lithium-ion distribution, and conductivity of Li7-3xGaxLa3Zr2O12 garnets is investigated, with the determined concentration and mobility of lithium ions shedding light on the origin of the high conductivity of Li7-3xGaxLa3Zr2O12. When the Ga concentration exceeds 0.20 Ga per formula unit, the garnet-type material is found to assume a cubic structure, but lower Ga concentrations result in the coexistence of cubic and tetragonal phases. Most lithium within Li7-3xGaxLa3Zr2O12 is found to reside at the octahedral 96h site, away from the central octahedral 48g site, while the remaining lithium resides at the tetrahedral 24d site. Such kind of lithium distribution leads to high lithium-ion mobility, which is the origin of the high conductivity; the highest lithium-ion conductivity of 1.46 mS/cm at 25 °C is found to be achieved for Li7-3xGaxLa3Zr2O12 at x = 0.25. Additionally, there are two lithium-ion migration pathways in the Li7-3xGaxLa3Zr2O12 garnets: 96h-96h and 24d-96h-24d, but the lithium ions transporting through the 96h-96h pathway determine the overall conductivity.

Gestational age-dependency of height and body mass index trajectories during the first 3 years in Japanese small-for-gestational age children.

Gestational age (GA) is thought to affect height growth in small-for-gestational age (SGA) children. However, the GA-specific trajectories in body mass index (BMI) and early appearances of adiposity rebound (AR) have not been fully investigated in a cohort of Japanese SGA children. A longitudinal cohort study was conducted with 1063 SGA children born in Kobe, Japan, with sufficient records from birth to 3 years of age. Subjects were divided into subgroups based on GA: 39–41 weeks GA (n = 723), 37–38 weeks GA (n = 256), 34–36 weeks GA (n = 62), and <34 weeks GA (n = 22). Height and BMI were assessed at 4 months, 9 months, 1.5 years, and 3 years of age. The catch-up rate for height was GA-dependent. Most children with 39–41 weeks GA (91%) caught up by 4 months of age; however, lower GA was associated with a slower elevation in the catch-up rate. The BMI trajectory during the first 3 years was also GA-dependent, with a change in GA dependency at a boundary of 37 weeks GA. Approximately 7% of SGA children had already developed AR before 3 years of age. In conclusion, growth patterns during infancy and early childhood in SGA children differ depending on GA.

Ga predeposition for the Ga-assisted growth of GaAs nanowire ensembles with low number density and homogeneous length

We present a novel two-step growth approach for the Ga-assisted growth of GaAs nanowires (NWs) by molecular beam epitaxy on Si. In the first step only Ga is deposited for the controlled formation of Ga droplets and in the second step NWs are grown from these droplets at lower Ga flux. This variation of the Ga flux leads to a decoupling of the formation of Ga droplets and the formation of NWs. Thus, the total density of crystal objects can be varied by only changing the parameters of the first step. Also, the NW length distribution of such an ensemble is more homogeneous. Annealing of the droplets can improve the homogeneity even further. The resulting GaAs NW ensembles are ideally suited for the subsequent growth of shell structures. Finally, our new approach enabled us to explore the nucleation of different crystalline objects and analyze the impact of the droplet size on the vertical yield of NWs in detail.

Elemental composition of zooplankton in the Kara Sea and the bays on the eastern side of Novaya Zemlya

The chemical composition of zooplankton in the Kara Sea Basin has been studied. Independent samplings of the open sea and the Blagopoluchie and Tsivol’ki bays of Novaya Zemlya testify to the similarity of the distribution pattern of all the studied elements. The chemical composition of samples is predominated by organic carbon (49.5 ± 4.8% of dry weight). The other most important constituent elements are Na, P, S, K, Mg, and Ca. Their average total concentrations are 4.82 ± 0.1%. From an analysis of the composition of major and trace elements of zooplankton in the Kara Sea and the bays of Novaya Zemlya, three groups of elements have been specified: with similar (Сorg, K, S, P, Al, Ti, Sc, Cd, Se, Cs, and Rb), lower (Na, Ca, Mg, Fe, Mn, Zn, Sr, Ba, B, Cu, Pb, Cr, Ni, V, Co, Sb, Mo, Ag, Be, Ga, and Hg), and higher (Li, As, and U) contents compared to their mean concentrations in ocean zooplankton.

Structural investigation and physical properties of Ga2O3–ZnO–P2O5 glasses

Glasses with composition xGa2O3–(50-x)ZnO–50P2O5 (where x=0–30) were prepared, and their basic physical characteristics (density, molar volume, glass transition and softening temperatures, thermal expansion coefficient and microhardness) were measured and discussed in connection with structural changes. Raman spectroscopy and 31P MAS NMR showed that increasing substitution of zinc(II) by gallium(III) shifts the basic structure of the glass from the prevailing metaphosphate (Q2) to pyrophosphate (Q1). With the highest content of gallium (x=30), orthophosphates (Q0) appear, which ultimately leads to crystallization of GaPO4 in the glassy matrix. Therefore, glass with x>25 could not be prepared, even with rapid cooling. 71Ga MAS NMR showed that at a lower Ga concentration, the dominating metaphosphate structure gallium was primarily six-coordinated, whereas with the dominating pyrophosphate structure (x≥10), four-fold coordinated Ga prevailed.

Avaliação do crescimento em longo prazo no recém‑nascido pré‑termo egresso de unidade de terapia intensiva neonatal

Objetivos: Avaliar a recuperação do crescimento em crianças que foram prematuras, nascidas com idade gestacional (IG) menor ou igual a 34 semanas, com idade entre 16 e 24 meses, egressas de unidade de terapia intensiva neonatal (UTIN) com tempo de internação maior ou igual a 4 semanas. Buscou-se também relacionar a recuperação do crescimento à história materna, às condições de nascimento, à alimentação e à intervenção terapêutica utilizada durante a internação em UTIN. Metodologia: O cenário de realização da pesquisa foi o Ambulatório de Prematuridade do Ambulatório de Especialidades “Dr. Nelson da Costa Chaves”, do Conjunto Hospitalar de Sorocaba (CHS), no período de agosto de 2014 a abril de 2015, identificando o lactente e, posteriormente, analisando diretamente os prontuários. Foi utilizado um formulário composto de cinco partes: história materna, condições de nascimento, intervenção terapêutica do recém-nascido (RN), alimentação e avaliação do crescimento da criança. Resultados: Dos 11 participantes, 2 não recuperaram o crescimento esperado, 2 não recuperaram o perímetro cefálico e apenas um não recuperou o peso mínimo esperado. Conclusão: Maior atenção deve ser dada ao acompanhamento pré-natal, principalmente devido às patologias que podem resultar em uma restrição de crescimento intrauterino e no trabalho de parto prematuro, gerando prejuízos muitas vezes irreparáveis aos RNs.

InGaAsP/InP integrated waveguide photodetector pair using quantum well intermixing

Quantum well intermixing using single layer ZrO2 capped annealing on InGaAsP/InP MQW has been used to achieve integrated two wavelength photodiode pair. The selective solubility of In and Ga in ZrO2 has been used for bandgap engineering. The top layers of the hetrostructure is chosen by lithography and etching into the same hetrostructure. The regions with lower desired bandgaps are chosen to be of lower Ga content. Comparison of different top layer and anneal conditions with respect to wavelength shift and surface quality is also shown. A uniform F ion implantation performed before the annealing has shown an increase of differential blue shift. Regions with up to a minimum of 60 nm InGaAs top layer have been shown to produce a differential bandgap change of 10 nm with no F ion implantation, and 30 nm with uniform F ion implantation (when annealed at 750 °C for 10 s with 300 nm ZrO2 cap).

Incidence, Risk Factors, and Morbidity of Acquired Postnatal Cytomegalovirus Infection Among Preterm Infants Fed Maternal Milk in a Highly Seropositive Population.

In preterm infants cytomegalovirus (CMV) infection acquired through maternal milk has been related to morbidity. However, infants who may receive higher titers of protective antibodies from highly seropositive mothers have not been studied in detail. A cohort of 188 ≤30-week-old infants was monitored from admission to discharge. CMV-DNA, hematology, liver enzymes, neutralizing antibodies, and CMV-DNA-lactia were tested periodically. Mothers of 157 infants (83.5%) were CMV-seropositive. A total of 24/157 (15.3%) infants became infected (95% confidence interval [CI], 9.8-22.6), particularly those of lower gestational age (GA; relative risk [RR], 2.32; 95% CI, 1.01-5.34 for 23-26 weeks). Low (<1:64) neutralizing antibody titers were similarly detected in CMV-infected and uninfected infants. Mean DNA-lactia in mothers was higher in CMV-infected than in uninfected infants (5.34 log vs 4.60 log). Clinical findings suggestive of CMV disease were similar in CMV-infected (50.0%) and CMV-uninfected (51.1%) infants. Although transitory, >2 laboratory test abnormalities occurred more frequently among CMV-infected (39.1%) than CMV-uninfected (2.1%) infants. More severe stages of retinopathy of prematurity (ROP) were found among CMV-infected infants (adjusted RR, 2.51; 95% CI, 1.07-5.91). Although deaths were more frequent among infected infants, none of the deaths could be directly attributed to CMV. Postnatal CMV infection acquired by exposure to raw maternal milk is very frequent among extremely premature newborns, being facilitated by high DNA-lactia and lower GA, regardless of maternally acquired neutralizing antibody levels. The association with advanced stages of ROP is a concern and needs to be further explored in larger studies.

Ectopic expression of a cytochrome P450 monooxygenase gene PtCYP714A3 from Populus trichocarpa reduces shoot growth and improves tolerance to salt stress in transgenic rice.

SummaryIn Arabidopsis thaliana and Oryza sativa, the cytochrome P450 (CYP) 714 protein family represents a unique group of CYP monooxygenase, which functions as a shoot‐specific regulator in plant development through gibberellin deactivation. Here, we report the functional characterizations of PtCYP714A3, an OsCYP714D1/Eui homologue from Populus trichocarpa. PtCYP714A3 was ubiquitously expressed with the highest transcript level in cambium–phloem tissues, and was greatly induced by salt and osmotic stress in poplar. Subcellular localization analyses indicated that PtCYP714A3‐YFP fusion protein was targeted to endoplasmic reticulum (ER). Expression of PtCYP714A3 in the rice eui mutant could rescue its excessive‐shoot‐growth phenotype. Ectopic expression of PtCYP714A3 in rice led to semi‐dwarfed phenotype with promoted tillering and reduced seed size. Transgenic lines which showed significant expression of PtCYP714A3 also accumulated lower GA level than did the wild‐type (WT) plants. The expression of some GA biosynthesis genes was significantly suppressed in these transgenic plants. Furthermore, transgenic rice plants exhibited enhanced tolerance to salt and maintained more Na+ in both shoot and root tissues under salinity stress. All these results not only suggest a crucial role of PtCYP714A3 in shoot responses to salt toxicity in rice, but also provide a molecular basis for genetic engineering of salt‐tolerant crops.

Semi-Prone Position Can Influence Variability in Respiratory Rate of Premature Infants Using Nasal CPAP

To determine the effect of positions (supine, lateral, semiprone) on the physiological parameters (HR, RR, SpO2) of premature infants receiving NCPAP who were non-oxygen-dependent and non-BPD, and to identify significant clinical changes associated with these variables. A crossover study design with three different positions in the assigned sequence (supine-supine, supine-lateral and supine-semiprone) was used, and each position was maintained for 1h. The subjects' vital signs were recorded 30 min after initiation of each position and measured for 30 min. Forty-seven infants with a median GA of 28.6 weeks (range 26-35) were studied, and their median BW was 1210g (range 776-2920). Overall, position-related effects showed significant difference in the variability in RR (OR=0.68; CI 0.51-0.89), with the variability in RR being significantly lower in the semiprone position. The lateral position was associated with increased RR (B=2.9; p=0.02). Previous use of ventilator (PUV) was associated with increased HR, whereas BW and GA were negatively associated with higher HR. Cesarean birth, use of surfactant and PUV were associated with lower SpO2, whereas BW and GA were correlated with higher SpO2. GA was identified as a protective factor, while PUV was a risk factor for the variability in both HR and SpO2. Premature infants receiving NCPAP sleeping in the semiprone position may have more stable RR, while the lateral position did not improve RR. Thus, the semiprone and supine positions may be considered preferable when positioning the monitored premature infants with NCPAP.

Surface contamination and electrical damage by focused ion beam: conditions applicable to the extraction of TEM lamellae from nanoelectronic devices

Focused ion beams (FIBs) are widely applied during manufacturing and for failure analysis, as a preparation tool for cross sectional scanning electron microscopy or for the extraction of lamellae for (scanning) transmission electron microscopy investigation of nanoelectronic devices. The impact of the ion beam milling on surface contamination is investigated by time-of-flight secondary ion mass spectroscopy, while the electrical surface damage is analyzed by a micro four-point probe. It is shown that the redeposition of milled Ga and Cu reaches levels below sensitivity (5 × 1010 at cm−2) at less than 10 mm from FIB structures while the lateral range of electrical surface damage is an order of magnitude smaller. The major source of the redeposition is the resputtering of sputtered material from the sample that was previously deposited on the SEM column. The 2D distribution of the redeposition is asymmetric and is simulated well based on a simplified model of the column and sample configuration. The electrical surface damage mainly relates to the beam tails. Pt deposits for surface protection require much lower Ga+ ion doses, and therefore have less impact on the wafer surface contamination. However, the range of electrical surface damage is larger for Pt deposits due to increased beam scattering in the low vacuum during the Pt deposition. With these contamination and damage levels and ranges, ‘wafer return’, i.e. continuing the wafer processing after the FIB, can be considered feasible for back-end of line processes with the loss of only the analyzed die or, potentially, also its neighbor. For front-end of line processes the acceptable contamination levels are more stringent and the feasibility of wafer return will be more process specific.

Effect of cooling rate after oxidation on hardness changes by firing simulation of Pd-CuGa-In metal-ceramic alloy

Effect of cooling rate after oxidation on hardness changes by firing simulation of Pd-Cu-Ga-In metal-ceramic alloy was examined by observing the change in hardness, crystal structure and microstructure. The hardness of specimen which was softened by ice quenching after oxidation increased apparently and such a high hardness was maintained during the subsequent firing stages. The hardness of specimen cooled at stage 0 after oxidation increased slighty and then the hardness decreased by wash treatment which is the first firing stage. Thereafter the low hardness was maintained during the subsequent firing stages. Specimen which was cooled by ice quenching after oxidation was softened due to homogenization of the microstructure, and then it was hardened due to precipitation during the simulated firing stages. In the specimens cooled at stage 0 or ice quenched after oxidation, Pd content was lower and Cu and Ga content was higher in precipitates than in the matrix. From the above results, cooling rate after oxidation did not affect the hardness changes of the metal substructure by firing simulation of Pd-Cu-Ga-In metal-ceramic alloy. Specimen which was ice quenched after oxidation was softened, which made processing easy.

Characterization of Cu(In,Ga)Se2 (CIGS) films with varying gallium ratios

Cu(In1−x,Gax)Se2 (CIGS) absorber layers were deposited on molybdenum (Mo) coated soda-lime glass substrates with varying Ga content (described as Ga/(In + Ga) ratios) with respect to depth. As the responsible mechanisms for the limitation of the performance of the CIGS solar cells with high Ga contents are not well understood, the goal of this work was to investigate different properties of CIGS absorber films with Ga/(In + Ga) ratios varied between 0.29 and 0.41 (as determined by X-ray florescence spectroscopy (XRF)) in order to better understand the role that the Ga content has on film quality. The Ga grading in the CIGS layer has the effect causing a higher band gap toward the surface and Mo contact while the band gap in the middle of the CIGS layer is lower. Also, a wider and larger Ga/(In + Ga) grading dip located deeper in the CIGS absorber layers tend to produce larger grains in the regions of the films that have lower Ga/(In + Ga) ratios. Moreover, it was found that surface roughness decreases from 51.2 nm to 41.0 nm with increasing Ga/(In + Ga) ratios. However, the surface roughness generally decreases if the Ga grading occurs deeper in the absorber layer.