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Atmospheric moisture is a sustainable clean water source that can solve the shortage of fresh water in arid areas. Herein a 2D covalent organic framework (COF-ok) was reported as a promising porous sorbent for solar-driven atmospheric water harvesting. COF-ok with ortho-ketoenamine linkage was extremely stable in harsh environment, including in boiling water, strong acids and bases. Because of the balanced hydrophilic and hydrophobic sites in channels, COF-ok showed a high water uptake of 0.33 g g

A theoretical study of modal gain in p-doped 1.3 mu m InAs/GaAs quantum dot (QD) lasers is presented. The expression of modal gain is derived, which includes an effective ratio that describes how many QDs contribute to the modal gain. The calculated results indicate that the modal gain with the effective ratio is much smaller than that without the effective ratio. The calculated maximum modal gain is is a good agreement with the experimental data. Furthermore, QDs with lower height or smaller aspect ratio are beneficial in achieving a larger maximum modal gain that leads to lower threshold current density and higher differential modal gain. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Multiple acyl-CoA dehydrogenase deficiency (MADD) is a metabolic disorder due to dysfunction of electron transfer flavoprotein (ETF) or ETF-ubiquinone oxidoreductase (ETF-QO). Mutations in ETFDH, encoding ETF-QO have been associated with both riboflavin-responsive and non-responsive MADD as well as a myopathic form of CoQ(10) deficiency, although pathomechanisms responsible for these different phenotypes are not well-defined. We performed mutation analysis in four Taiwanese MADD patients. Three novel ETFDH mutations were identified in four patients and all harbored the p.A84T mutation. Muscle CoQ(10) levels and respiratory chain activities measured in two patients were normal. Three patients improved on riboflavin together with carnitine. Our results show that not all MADD patients have CoQ(10) deficiency. Based upon our data, riboflavin and carnitine may be the first-line treatment for MADD.

Maple syrup urine disease (MSUD) is an autosomal recessive inborn error disorder derived from the accumulation of the branched-chain amino acids (BCAAs) leucine, isoleucine and valine. Either the E1alpha, E1beta or DBT (E2) genes are responsible for this neurometabolic disease. Here, we report the identification and characterization of a novel E2 gene 4.7 kb deletion as a rare nonhomologous recombination of the long interspersed nuclear elements 1 (LINE-1) in intron 10 and the Alu in the 3' UTR of the E2 gene from three classic MSUD patients of the Austronesian aboriginal tribe Paiwan in Taiwan. The E2 gene 4.7 kb deletion accounted for five out of six alleles in the three unrelated Paiwanese MSUD patients, indicating a founder effect. Carrier-frequency study revealed one deleted heterozygote out of 101 normal Paiwanese. As the nine Taiwanese Austronesian aboriginal tribes share a common origin, this E2 4.7 kb deletion may be preserved in some of the other Austronesian aboriginal tribes of Taiwan. This is the first comprehensive genetics study of MSUD in the Austronesian tribal groups as well as in Taiwan.

In this contribution we report the research and development of 1.55 mu m InGaAsP/InP gain-coupled DFB laser with an improved injection-carrier induced grating and of high performance 1.3 mu m and 1.55 mu m InGaAsP/InP FP and DFB lasers for communications. Long wavelength strained MQW laser diodes with a very low threshold current (7-10 mA) have been fabricated. Low pressure MOVPE technology has been employed for the preparation of the layered structure. A novel gain-coupled DFB laser structure with an improved injection-carrier modulated grating has been proposed and fabricated. The laser structures have been prepared by hybrid growth of MOVPE and LPE techniques and reasonably good characteristics have been achieved for resultant lasers. High performance 1.3 mu m and 1.55 mu m InGaAsP/InP DFB lasers have successfully been developed for CATV and trunk line optical fiber communication.

We have fabricated 1.3-mum InAs-GaAs quantum-dot (QD) lasers with and without p-type modulation doping and their characteristics have been investigated. We find that introducing p-type doping in active regions can improve the temperature stability of 1.3-mum InAs-GaAs QD lasers, but it does not increase the saturation modal gain of the QD lasers. The saturation modal gain obtained from the two types of lasers is identical (17.5 cm-1 ). Moreover, the characteristic temperature increases as cavity length increases for the two types of lasers, and it improves more significantly for the lasers with p-type doping due to their higher gain.

High brightness InAs/GaAs quantum dot tapered lasers at 1.3μm were first developed with high temperature stability. The devices consisted of a straight index-guided section formed by a ridge waveguide (RW) and a gain-guided tapered section. To enhance the mode filtering, a pair of cavity spoiling grooves had been included. For two different laser lengths L =1.5mm and 3mm with a constant full taper angle φ TR = 4°, the length of the ridge waveguide section L 2 was varied for 1.5 mm long devices, whose L 2 was 0.5mm and 1 mm, respectively. In case of L=3 mm, the L 2 was fixed at 1mm. For above-mentioned geometries, the light power (P) - current (I) characteristics and the beam quality factor (M 2 ) were presented. The lasers with a smaller L 2 have higher threshold current due to the larger area of the tapered section at fixed total length. The beam quality can be improved with longer L and L 2 at fixed total length L. The M 2 was lower than the value of 3 measured under different light power, moreover, the M 2 increased with light power increasing. We also measured temperature dependence of threshold current for two kinds of lasers with L=1.5 and 3 mm. The threshold current was almost constant over a temperature range from 30 to 70°C. It is of important significance for the practical application because that the temperature range overlapped with the operating temperature range. In addition, temperature dependence of the M 2 for the lasers with L=3 mm was also studied.

Mitochondrial diseases comprise a group of complex and heterogeneous genetic disorders. Variable clinical features present a major challenge in pediatric diagnoses. From January 1984-June 2009, 69 patients were diagnosed with either syndromic mitochondrial diseases or nonsyndromic mitochondrial diseases. Clinical manifestations, laboratory findings, and histopathologic results differentiating syndromic from nonsyndromic mitochondrial diseases were analyzed by χ 2 test, with cutoff significance at P = 0.05. The commonest clinical manifestation involved central nervous system signs (88.4%). A comparison of central nervous system signs in syndromic vs nonsyndromic mitochondrial diseases revealed significant differences in terms of headache, external ocular motility, and apnea ( P 0.05). A comparison of organ systems revealed a significant difference for signs of the cardiovascular system. Elevated initial blood lactate levels were evident in 40.6% of patients, and 84.8% produced abnormal results after oral glucose challenge. Ragged red fibers were observed in 51.6% of patients. The positive rate of mitochondrial gene mutation was 27.5%. Age and disease were directly related: the younger the age at initial disease onset, the higher the frequency of mortality and morbidity. Notorious variability in the presentation of mitochondrial diseases exists in all pediatric subspecialties. Greater familiarity with those signs will facilitate more accurate diagnoses.

The problem of conventional light emitting diodes (LEDs) was analyzed. A novel tunnel-regenerated multiple-active-region light-emitting diode with high quantum efficiency and high brightness has been proposed and fabricated. We have proved theoretically that the efficiency of the electrical luminescence and the on-axis luminous intensity of such novel LEDs scaled linearly approximately with the number of the active regions. The on-axis luminous intensity of such novel LED with only 3 /spl mu/m GaP current spreading layer has exceeded 5cd at 20 mA DC operation under 15/spl deg/ package. The ultrahigh quantum efficiency and ultrahigh brightness LED under the low injection level was realized.

We describe the clinical characteristics of 5 Taiwanese children with glutaric aciduria type I treated in a single medical center. Macrocephaly was present in 5 of these patients, psychomotor retardation in 4, and neurological regression in 2. Diagnosis was made prenatally in 1 patient due to an affected sibling. Low lysine/tryptophan formula, carnitine, and vitamin B2 were given to all patients. All patients disliked and could not adhere to the special formula and medications. Four older patients had neurological deficits prior to the start of the regimen. Among them, 1 died of sepsis and malnutrition. Only the prenatally diagnosed child did well at age 22 months. Mutational analysis, performed by polymerase chain reaction and sequencing, revealed an IVS10-2AC defect in all 5 patients, and 2 siblings were homozygous. In addition, 2 novel mutations were detected. We conclude that GA I might not be as rare in Taiwan as previously thought. IVS10-2AC is a common mutation in the Taiwanese population, whose genotypes are quite different from those of Caucasians.

A 22-year-old woman had suffered from several episodes of acute pancreatitis since the age of 11. Other than exercise intolerance since early childhood, her psychomotor development was normal. At age 21, she experienced two episodes of generalized muscle weakness including acute respiratory failure and hepatomegaly. Liver biopsy indicated fatty metamorphosis, and muscle biopsy revealed vacuolar myopathy with lipid accumulation. Biochemical investigations demonstrated elevated serum creatine kinase and elevated 2-hydroxylglutaric, pyruvic, ethylmalonic, hippuric, adipic, and seburic acids in urinary organic acid analysis. These findings confirmed the diagnosis of glutaric aciduria type II. Although acute pancreatitis in glutaric aciduria type II has been reported previously, this is the first reported case of recurrent pancreatitis occurring in glutaric aciduria type II. We treated the patient with l-carnitine and riboflavin. As of the latest follow-up 2.5 years later, the patient has had no further episodes of muscle weakness or pancreatitis. We suggested analyzing urine organic acid when lipid storage myopathy is suspected.

Tunnel-regenerated multiple-active-region (TRMAR) light-emitting diodes (LEDs) with high quantum efficiency and high brightness have been proposed and fabricated. We have proved experimentally that the efficiency of the electrical luminescence and the on-axis luminous intensity of such TRMAR LEDs scaled linearly approximately with the number of the active regions. The on-axis luminous intensity of such TRMAR LEDs with only 3 mum GaP current spreading layer have exceeded 5 cd at 20 mA dc operation under 15 degrees package. The high-quantum-efficiency and high-brightness LEDs under the low injection level were realized. (C) 2001 American Institute of Physics.

In this letter, we present a facet coating design to delay the excited state (es) lasing for 1310 nm inas/gaas quantum dot lasers. the key point of our design is to ensure that the mirror loss of es is larger than that of the ground state by decreasing the reflectivity of the es. in the facet coating design, the central wavelength is at 1480 nm, and the high- and low-index materials are ta2o5 and sio2, respectively. compared with the traditional si/sio2 facet coating with a central wavelength of 1310 nm, we have found that with the optimal design the turning temperature of the es lasing has been delayed from 90 to 100 degrees c for the laser diodes with cavity length of 1.2 mm. furthermore, the characteristic temperature (t-0) of the laser diodes is also improved.

Photoluminescence of NInGaAsP multiepilayers has been observed. The wafers used have the structure of NInGaAsP active layer (Eg∼0.95eV) /NInGaAsP confinement layer (Eg∼1.2eV) /NInP substrate. Several radiation emission peaks can be seen in the photoluminescence spectra, which are identified as band to band recombination and recombination between electrons in the conduction band and holes in the split-off valence band in both the active layer and the confinement layer respectively. The fact that all layers used are N-type material excludes any uncertainties resulting from electron leakage and provides new evidence that hole leakage occurs in present structures and is enhanced by the split-off valence band.