Biosynthesis of the activated sulfate donor, adenosine 3'-phosphate 5'-phosphosulfate, involves the sequential action of two enzyme activities: ATP sulfurylase, which catalyzes the formation of adenosine 5'-phosphosulfate (APS) from ATP and free sulfate, and APS kinase, which subsequently phosphorylates APS to produce adenosine 3'-phosphate 5'-phosphosulfate. Oligonucleotide primers were derived from a human infant brain-expressed sequence tag putatively encoding a portion of APS kinase. Using these primers, reverse transcriptase-polymerase chain reaction was performed on mRNA from neonatal normal mice resulting in amplification of a 127-bp DNA fragment. This fragment was subsequently used to screen a mouse brain lambda gt11 cDNA library, yielding a 2.2-kb clone. Primers were designed from the 5'-end of the 2.2-kb clone, and 5'-rapid amplification of cDNA ends was used to obtain the translation start site. Sequence from the overlapping clones was assembled into a 2475-bp composite sequence, which contains a single open reading frame that translates into a 624-deduced amino acid sequence. Northern blots of total RNA from neonatal mice yielded a single message species at approximately 3.3 kb. Southern blot of genomic DNA digested with several restriction enzymes suggested the gene is present as a single copy. Comparison against sequence data bases suggested the composite sequence was a fused sulfurylase-kinase product, since the deduced amino acid sequence showed extensive homology to known separate sequences of both ATP sulfurylase and APS kinase from several sources. The first 199 amino acids corresponded to APS kinase sequence, followed by 37 distinct amino acids, which did not match any known sequence, followed by 388 amino acids that are highly homologous to known ATP sulfurylase sequences. Finally, recombinant enzyme expressed in COS-1 cells exhibited both ATP sulfurylase and APS kinase activity.

In order to enhance the visible-light transmittance while reducing the insulator–metal transition (IMT) temperature, Hf–W co-doping is designed for modification of VO2. We grow high-quality HfxWyV1−x−yO2 (HfWVO2) alloy films on c-plane sapphire substrates by pulsed laser deposition, and test structural, electrical, and optical properties of the films by various techniques. The Hf–W co-doped VO2 films exhibit outstanding thermochromic performances with a high luminous transmittance up to 41.1%, a fairly good near-infrared modulation capacity of 13.1%, and a low phase transition temperature of 38.9 °C. The enhanced luminous transmittance along with reduced IMT temperature in HfWVO2 is attributed to the co-doping synergetic effect of Hf and W, which effectively improves the optical bandgap and donates extra electrons into the system, respectively, while largely retaining the near-infrared modulation capacity of VO2. Our work provides an effective strategy in tailoring VO2 toward practical smart-coating applications by Hf–W co-doping.

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The past few decades have witnessed an ever-growing scholarly interest in microwave dielectric ceramics with the rapid development of telecommunication. [1][2][3][4] Recently, there is a strong ongoing search for dielectric ceramics with a dielectric constant (ε r ) less than 15, a low dielectric loss (tan δ = 1/Q), and a near-zero temperature coefficient (τ f ) to meet the demands for microwave substrate applications. 5,6 Although traditional inorganic substrates such as Al 2 O 3 possess excellent dielectric properties, the exploration for novel materials with superior dielectric properties and sintering behaviors continues today.Pyrophosphates belong to typical low-permittivity compounds, in which M 2 P 2 O 7 possesses two kinds of structure according to the ionic radius of M that is a divalent cation. 7 The structure is recognized as thortveitite-type if the M ionic radius is less than 0.97 Å (M = Mn, Mg, Zn), while the structure converts to dichromate-type if the M ionic radius is larger than 0.97 Å (M = Ca, Sr, Ba). The dependence of dielectric properties on the phase composition of M 2 P 2 O 7 (M = Ca, Sr, Ba, Mn, Mg, Zn) was investigated by Bian et al. 8 and dielectric properties were ε r = 6.1~8.4, Qf = 12300~53500 GHz, and τ f = −23~−746 ppm/°C. Sutapun et al. 9 studied the substitution effect of Zn 2+ at the Mn site of Mn 2 P 2 O 7 , and found that the dopants of Zn 2 P 2 O 7 were diffused completely into the Mn 2 P 2 O 7 structure, forming solid solutions.In recent years, many compounds with the general formula of M2M1P 2 O 7 have been reported with excellent microwave dielectric properties and low sintering temperatures. Complex pyrophosphates compounds M2M1P 2 O 7 (M2 = Ca, Sr; M1 = Zn, Cu) were investigated as low temperature cofired ceramic (LTCC) materials due to their intrinsic low sintering temperatures. 10 In the past, the work of BaZnP 2 O 7 was mainly focused on the luminescence properties. 11,12 In 2016, Xie et al. 13 prepared BaZnP 2 O 7 ceramics through solid-state reaction and reported its dielectric properties: ε r = 8.4, Qf = 27925 GHz, and τ f = −56.7 ppm/°C. However, there are

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