Whole-genome sequencing of a worldwide collection of sugarcane cultivars (Saccharum spp.) reveals the genetic basis of cultivar improvement.

Sugarcane is the main source of sugar worldwide, and 80% of the sucrose production comes from sugarcane. However, the genetic differentiation and basis of agronomic traits remain obscure. Here, we sequenced the whole-genome of 219 elite worldwide sugarcane cultivar accessions. A total of approximately 6 million high-quality genome-wide single nucleotide polymorphisms (SNPs) were detected. A genome-wide association study identified a total of 2198 SNPs that were significantly associated with sucrose content, stalk number, plant height, stalk diameter, cane yield, and sugar yield. We observed homozygous tendency of favor alleles of these loci, and over 80% of cultivar accessions carried the favor alleles of the SNPs or haplotypes associated with sucrose content. Gene introgression analysis showed that the number of chromosome segments from Saccharum spontaneum decreased with the breeding time of cultivars, while those from S. officinarum increased in recent cultivars. A series of selection signatures were identified in sugarcane improvement procession, of which 104 were simultaneously associated with agronomic traits and 45 of them were mainly associated with sucrose content. We further proposed that as per sugarcane transgenic experiments, ShN/AINV3.1 plays a positive role in increasing stalk number, plant height, and stalk diameter. These findings provide comprehensive resources for understanding the genetic basis of agronomic traits and will be beneficial to germplasm innovation, screening molecular markers, and future sugarcane cultivar improvement.

Polymorphism in the Ruddlesden-Popper Nickelate La3Ni2O7: Discovery of a Hidden Phase with Distinctive Layer Stacking.

We report the discovery of a novel form of Ruddlesden-Popper (RP) nickelate that stands as the first example of long-range, coherent polymorphism in this class of inorganic solids. Rather than the well-known, uniform stacking of perovskite blocks ubiquitously found in RP phases, this newly discovered polymorph of the bilayer RP phase La3Ni2O7 adopts a novel stacking sequence in which single-layer and trilayer blocks of NiO6 octahedra alternate in a "1313" sequence. Crystals of this new polymorph are described in space group Cmmm, although we note evidence for a competing Imam variant. Transport measurements at ambient pressure reveal metallic character with evidence of a charge density wave transition with an onset at T ≈ 134 K. The discovery of such polymorphism could reverberate to the expansive range of science and applications that rely on RP materials, particularly the recently reported signatures of superconductivity in bilayer La3Ni2O7 with Tc as high as 80 K above 14 GPa.

Characterization and expression profiles of the B-box gene family during plant growth and under low-nitrogen stress in Saccharum.

BACKGROUND: B-box (BBX) zinc-finger transcription factors play crucial roles in plant growth, development, and abiotic stress responses. Nevertheless, little information is available on sugarcane (Saccharum spp.) BBX genes and their expression profiles. RESULTS: In the present study, we characterized 25 SsBBX genes in the Saccharum spontaneum genome database. The phylogenetic relationships, gene structures, and expression patterns of these genes during plant growth and under low-nitrogen conditions were systematically analyzed. The SsBBXs were divided into five groups based on phylogenetic analysis. The evolutionary analysis further revealed that whole-genome duplications or segmental duplications were the main driving force for the expansion of the SsBBX gene family. The expression data suggested that many BBX genes (e.g., SsBBX1 and SsBBX13) may be helpful in both plant growth and low-nitrogen stress tolerance. CONCLUSIONS: The results of this study offer new evolutionary insight into the BBX family members in how sugarcane grows and responds to stress, which will facilitate their utilization in cultivated sugarcane breeding.

C9orf72 poly(PR) aggregation in nucleus induces ALS/FTD-related neurodegeneration in cynomolgus monkeys.

Poly(PR) is a dipeptide repeat protein comprising proline and arginine residues. It is one of the translational product of expanded G4C2 repeats in the C9orf72 gene, and its accumulation is contributing to the neuropathogenesis of C9orf72-associated amyotrophic lateral sclerosis and/or frontotemporal dementia (C9-ALS/FTD). In this study, we demonstrate that poly(PR) protein alone is sufficient to induce neurodegeneration related to ALS/FTD in cynomolgus monkeys. By delivering poly(PR) via AAV, we observed that the PR proteins were located within the nucleus of infected cells. The expression of (PR)50 protein, consisting of 50 PR repeats, led to increased loss of cortical neurons, cytoplasmic lipofuscin, and gliosis in the brain, as well as demyelination and loss of ChAT positive neurons in the spinal cord of monkeys. While, these pathologies were not observed in monkeys expressing (PR)5, a protein comprising only 5 PR repeats. Furthermore, the (PR)50-expressing monkeys exhibited progressive motor deficits, cognitive impairment, muscle atrophy, and abnormal electromyography (EMG) potentials, which closely resemble clinical symptoms seen in C9-ALS/FTD patients. By longitudinally tracking these monkeys, we found that changes in cystatin C and chitinase-1 (CHIT1) levels in the cerebrospinal fluid (CSF) corresponded to the phenotypic progression of (PR)50-induced disease. Proteomic analysis revealed that the major clusters of dysregulated proteins were nuclear-localized, and downregulation of the MECP2 protein was implicated in the toxic process of poly(PR). This research indicates that poly(PR) expression alone induces neurodegeneration and core phenotypes associated with C9-ALS/FTD in monkeys, which may provide insights into the mechanisms of disease pathogenesis.

Sr(Ag1-x Lix )2 Se2 and [Sr3 Se2 ][(Ag1-x Lix )2 Se2 ] Tunable Direct Band Gap Semiconductors.

Synthesizing solids in molten fluxes enables the rapid diffusion of soluble species at temperatures lower than in solid-state reactions, leading to crystal formation of kinetically stable compounds. In this study, we demonstrate the effectiveness of mixed hydroxide and halide fluxes in synthesizing complex Sr/Ag/Se in mixed LiOH/LiCl. We have accessed a series of two-dimensional Sr(Ag1-x Lix )2 Se2 layered phases. With increased LiOH/LiCl ratio or reaction temperature, Li partially substituted Ag to form solid solutions of Sr(Ag1-x Lix )2 Se2 with x up to 0.45. In addition, a new type of intergrowth compound [Sr3 Se2 ][(Ag1-x Lix )2 Se2 ] was synthesized upon further reaction of Sr(Ag1-x Lix )2 Se2 with SrSe. Both Sr(Ag1-x Lix )2 Se2 and [Sr3 Se2 ][(Ag1-x Lix )2 Se2 ] exhibit a direct band gap, which increases with increasing Li substitution (x). Therefore, the band gap of Sr(Ag1-x Lix )2 Se2 can be precisely tuned via fine-tuning x that is controlled by only the flux ratio and temperature.

Genome-wide characterization and expression analysis of the growth-regulating factor family in Saccharum.

BACKGROUND: Growth regulating factors (GRFs) are transcription factors that regulate diverse biological and physiological processes in plants, including growth, development, and abiotic stress. Although GRF family genes have been studied in a variety of plant species, knowledge about the identification and expression patterns of GRFs in sugarcane (Saccharum spp.) is still lacking. RESULTS: In the present study, a comprehensive analysis was conducted in the genome of wild sugarcane (Saccharum spontaneum) and 10 SsGRF genes were identified and characterized. The phylogenetic relationship, gene structure, and expression profiling of these genes were analyzed entirely under both regular growth and low-nitrogen stress conditions. Phylogenetic analysis suggested that the 10 SsGRF members were categorized into six clusters. Gene structure analysis indicated that the SsGRF members in the same group were greatly conserved. Expression profiling demonstrated that most SsGRF genes were extremely expressed in immature tissues, implying their critical roles in sugarcane growth and development. Expression analysis based on transcriptome data and real-time quantitative PCR verification revealed that GRF1 and GRF3 were distinctly differentially expressed in response to low-nitrogen stress, which meant that they were additional participated in sugarcane stress tolerance. CONCLUSION: Our study provides a scientific basis for the potential functional prediction of SsGRF and will be further scrutinized by examining their regulatory network in sugarcane development and abiotic stress response, and ultimately facilitating their application in cultivated sugarcane breeding.

Temporal Progress and Spatial Patterns of Northern Corn Leaf Blight in Corn Fields in China.

Northern corn leaf blight (NCLB), caused by Exserohilum turcicum, is a devastating disease of corn in China. To enhance our understanding of NCLB epidemiology, the temporal progress and spatial patterns of NCLB were investigated. A susceptible corn cultivar, Xianyu 335, was planted in a field in Beijing in 2016 and 2017. Leaf lesions of NCLB on each plant were counted twice a week during the growing seasons. In addition, temporal disease progress was monitored for 8 weeks in three commercial corn fields in each of Yanqing, Miyun, Daxing, and Haidian Districts of Beijing in 2017, and the spatial patterns of diseased plants and NCLB lesion counts per plant were assessed in three commercial corn fields with moderate to high NCLB incidence in Yanqing District. The results demonstrated that a logistic model was the most appropriate to describe the temporal progress of NCLB incidence. The initial disease incidence was the key factor affecting disease epidemics under various conditions in the four districts of Beijing during the study. The higher the initial incidence of NCLB, the higher the final incidence. Thus, the earlier in the season NCLB incidence attained 1%, the higher was the final disease incidence. Greater than 1.0 variance-to-mean ratios suggested that the leaf lesions of NCLB tended to be aggregated on a plant. According to results from join-counts, variance of moving window averages, and semivariogram analysis, diseased corn plants and lesion numbers on each plant were aggregated in the field. The clustered pattern of NCLB lesions and infected plants suggested that conidia produced locally on diseased plants were important for disease spread within the field. The aggregated pattern of diseased plants suggested that plants should be sampled from more sites in a field to accurately estimate incidence of NCLB.

The Coverage of Soft-Tissue Defects Around the Foot and Ankle Using Free or Local Flaps: A Comparative Cohort Study.

BACKGROUND: The purpose of this study was to compare the reconstructive outcomes of soft-tissue defects around foot and ankle with local or free flaps and attempt to provide an optimal strategy for these patients in comparison with the conventional guidelines. METHODS: A retrospective review of all continuous patients with foot and ankle reconstruction using different flaps from 2010 to 2018 was performed. Based on the flap types, the patients were divided into 2 groups: local flap group and free flap group. Outcomes were assessed according to the flap survival rate, recipient complications, aesthetic outcomes, and donor-site complications. RESULT: A total of 130 flaps including 47 free flaps and 83 local flaps were collected. There was no difference in flap survival rate between the 2 groups; however, a significant difference in aesthetic outcomes was noted between them: the free flap group presented a better overall aesthetic outcomes in comparison with the local flap group in terms of color and contour match. Moreover, local flaps had more donor-site morbidities including the need for skin grafting and wound infection. CONCLUSIONS: Free flaps in wound coverage of foot and ankle can achieve better outcomes than local flaps in terms of recipient benefits and donor-site compromise with a comparable flap survival rate.

Second-Harmonic Generation and Photoluminescence Properties of Sn(II)- and Bi(III)-Based Lone Pair Cation-Pyridine Dicarboxylate Coordination Compounds.

Lone pair cation-based novel coordination compounds Sn[(pdc)(H2O)] (Sn-I) and (H2bpy)[Bi(pdc)2(Hpdc)]·5H2O (Bi-I) (pdc = pyridine-2,6-dicarboxylate; bpy = 4,4'-bipyridine) were synthesized through mild hydrothermal reactions. While Sn-I crystallizing in the polar space group, Pca21, exhibits a helical chain structure consisting of SnO3N distorted seesaws, 2,6-pdc linkers, and water molecules, Bi-I crystallizing in the centrosymmetric (CS) space group, P1̅, reveals a pseudo-3D network composed of BiO5N3 polyhedra, 2,6-pdc ligands, H2bpy2+ cations, and isolated H2O molecules. The lone cations Sn2+ and Bi3+ in the title compounds are in a highly deformed polyhedral environment. The single-crystal-to-single-crystal transformation from Sn-I to the anhydrous Sn[(pdc)] (Sn-II) with the polar noncentrosymmetric structure was successfully achieved upon heating crystals of Sn-I. UV-vis diffuse reflectance spectra indicate that the introduction of Sn2+ or Bi3+ red-shifts the adsorption edges upon coordination. Powder second-harmonic generation (SHG) measurements indicate that Sn-I and Sn-II are type-I phase-matchable and exhibit SHG intensity of ca. 15 and 35 times that of α-SiO2, respectively. Solid state photoluminescence (PL) measurements indicate that Bi-I is an excellent green emitting phosphor with the quantum efficiency up to 26% and outstanding decay lifetime of 1.82 ms at room temperature.

Lead Mixed Oxyhalides Satisfying All Fundamental Requirements for High-Performance Mid-Infrared Nonlinear Optical Materials.

To design high-performance mid-infrared (mid-IR) nonlinear optical (NLO) materials, we have focused on the combination of a heavy metal lone pair cation, Pb2+ and mixed oxyhalides. A systematic investigation in PbO-PbCl2 -PbBr2 system led us to discover the first examples of NLO lead mixed oxyhalides, namely, Pb13 O6 Cl4 Br10 , Pb13 O6 Cl7 Br7 , and Pb13 O6 Cl9 Br5 . All the reported materials have remarkably comprehensive properties including broad IR transparency (up to 14.0 µm), qualified second harmonic generation (SHG) responses (0.6-0.9×AgGaS2 ), wide band gaps (3.05-3.21 eV), and ease of crystal growth. Interestingly, a centimeter-sized single crystal (2.9×1.3×0.5 cm3 ) of Pb13 O6 Cl9 Br5 revealing a wide transparent range (0.384-14.0 µm) and high laser damage threshold (LDT) (14.6×AgGaS2 ) has been successfully grown in an open system. The study suggests that all the reported mixed oxyhalides are outstanding candidates for mid-IR NLO materials.

Pb18 O8 Cl15 I5 : A Polar Lead Mixed Oxyhalide with Unprecedented Architecture and Excellent Infrared Nonlinear Optical Properties.

To develop high-performance nonlinear optical (NLO) materials for infrared (IR) applications, we have applied a rational element-composition design strategy and investigated the unexplored PbO-PbCl2 -PbI2 system. By doing so, we discovered a new polar lead mixed oxyhalide, Pb18 O8 Cl15 I5 , the first synthetic metal oxyhalide combining both Cl- and I- . Pb18 O8 Cl15 I5 reveals an unprecedented structural feature with two different dimensional types of oxocentered Pb-O units, namely, [O4 Pb8 ]8+ clusters and [OPb2 ]2+ chains. Centimeter-sized single crystals of Pb18 O8 Cl15 I5 have been successfully grown under ambient conditions. Remarkably, Pb18 O8 Cl15 I5 satisfies all fundamental yet rigorous criteria for high-performance IR NLO materials, exhibiting the widest IR transparency (up to 16.0 µm) among oxide-based crystals, strong second-harmonic generation response (1.05×AgGaS2 ), superior birefringence (0.086 at 636 nm), and a high laser-induced damage threshold (8.5×AgGaS2 ).

Rational Design via Synergistic Combination Leads to an Outstanding Deep-Ultraviolet Birefringent Li2Na2B2O5 Material with an Unvalued B2O5 Functional Gene.

Birefringent materials, the key components in modulating the polarization of light, are of great importance in optical communication and the laser industry. Limited by their transparency range, few birefringent materials can be practically used in the deep ultraviolet (DUV, λ < 200 nm) region. Different from the traditional BO3- or B3O6-based DUV birefringent crystals, we propose a new functional gene, the B2O5 unit, for designing birefringent materials. Excitingly, the synergistic combination of Li4B2O5 and Na4B2O5 generates a new compound, Li2Na2B2O5, with enhanced optical properties. The Li2Na2B2O5 crystal with a size of up to 35 × 15 × 5 mm3 was grown by the top-seeded solution growth (TSSG) method, and its physicochemical properties were systematically characterized. Li2Na2B2O5 features a large amount of birefringence (0.095@532 nm), a short DUV cutoff edge (181 nm) with a high laser-induced damage threshold (LDT, 7.5 GW/cm2 @1064 nm, 10 ns), favorable anisotropic thermal expansion (αa/αb = 5.6), and the lowest crystal growth temperature (<609 °C) among the commercial birefringent crystals. Moreover, the influences of the B2O5 structural configurations on the optical anisotropy were explored. The fascinating experimental results will provide a prominent DUV birefringent crystal and an effective synthesis strategy, which can facilitate the design of DUV birefringent materials.

Risk Factors Associated With Postoperative Recurrence in Patients With Tenosynovial Giant Cell Tumor of the Hand: A Retrospective Cohort Study.

Identification of risk factors for recurrence of tenosynovial giant cell tumors of the hand is crucial to provide adequate preoperative counseling and tailor surgical treatment. However, the risk factors are still controversial, which are the subject of this research.Recently, we conducted a retrospective cohort study of 135 consecutive patients with giant cell tumors of the tendon sheath of the hand from January 2010 to July 2016. All patients underwent surgical excision, received necessary imaging examinations, and had routine follow-up and thus were identified as those who had recurrence by confirmation of reoperation, and the duration ranged from 24 to 103 months (mean, 53.5 ± 21.4 months). There were 14 local recurrences (10.4%) within 6 to 24 months, respectively, after surgery. Data pertaining to sex, age, tumor sites, tumor size, tumor number, course of disease, bone erosion, tumor growth patterns, anesthesia mode, and the surgeon's experience were all extracted, and Cox regression models were used to estimate recurrence rate with adjustment for potential confounders.According to the Cox regression analysis, the recurrence rate after surgery was significantly higher in patients with a diffused form than in those with a localized one (P = 0.001); in addition, patients with 2 or more tumors had a much higher postoperative recurrence rate than did those with only 1 tumor (P = 0.023).This study suggested that the recurrence rate of tenosynovial giant cell tumors of the hand was closely related to the tumor number and tumor growth patterns.

Evaluation of Rice Responses to the Blast Fungus Magnaporthe oryzae at Different Growth Stages.

Rice blast, caused by the fungus Magnaporthe oryzae, is the most damaging disease for rice worldwide. However, the reactions of rice to M. oryzae at different growth stages are largely unknown. In the present study, two temperate japonica rice cultivars, M-202 and Nipponbare, were inoculated synchronously at different vegetative growth stages, V1 to V10. Plants of M-202 at each stage from V1 to reproductive stage R8 were inoculated with M. oryzae race (isolate) IB-49 (ZN61) under controlled conditions. Disease reactions were recorded 7 days postinoculation by measuring the percentage of diseased area of all leaves, excluding the youngest leaf. The results showed that the plants were significantly susceptible at the V1 to V4 stages with a disease severity of 26.7 to 46.8% and disease index of 18.62 to 37.76 for M-202. At the V1 to V2 stages, the plants were significantly susceptible with a disease a severity of 28.6 to 39.3% and disease index of 23.65 to 29.82 for Nipponbare. Similar results were observed when plants of M-202 were inoculated at each growth stage with a disease severity of 29.7 to 60.6% and disease index of 21.93 to 59.25 from V1 to V4. Susceptibility decreased after the V5 stage (severity 4.6% and index 2.17) and became completely resistant at the V9 to V10 stages and after the reproductive stages, suggesting that plants have enhanced disease resistance at later growth stages. These findings are useful for managing rice blast disease in commercial rice production worldwide.

The management of degloving injuries of the limb with full thickness skin grafting using vacuum sealing drainage or traditional compression dressing: A comparative cohort study.

BACKGROUND: Degloving injuries of the limb are severe and frequently underrated. Few researches are available comparing the results of reattachment of the degloved skin grafts with the vacuum sealing drainage technique and the traditional compression dressing method. In this study, we aimed to compare the treatment outcomes of these two approaches. METHODS: Eighty-three consecutive patients were treated for degloving injury of the limb. Based on the treatment approach, the patients were divided into vacuum sealing drainage group (VSD group, n = 55) and traditional compression dressing group (TCD group, n = 28). After reattachment, the degloved skin was secured with stitches and compressed with VSD or TCD. The outcomes were mainly assessed based on the percentage of skin graft take. RESULT: In VSD group, there were excellent results in 18, fair in 9 and poor in 28, respectively; In TCD group, there were excellent results in 11, fair in 10 and poor in 7, respectively. Statistically, no significant difference was found between two groups in terms of the category of excellent results. However, significant higher incidence of poor results with necrotic areas exceeding 50% was observed in the VSD group than that in the TCD group. In addition, although the duration of hospitalization in the VSD group was shorter than that in the TCD group, the medical supply costs and total costs were much higher than that of the TCD group. CONCLUSION: VSD and TCD are equally effective in the management of degloving injuries of the limb; however, VSD technique may potentially have a higher risk of poor results with increased hospital charges. The traditional approach still has its merits in clinical practice, especially in rural hospitals when VSD is not available or unaffordable.

Designing an Excellent Deep-Ultraviolet Birefringent Material for Light Polarization.

Owing to their vital role in creating and controlling polarized light, birefringent materials are used extensively in various advanced optical systems which in turn impact a large, rapidly increasing range of applications in science and technology. Currently, the fairly small birefringence of MgF2 and the low transmittance of α-BaB2O4 (α-BBO) hinder their efficient application for wavelength below 200 nm. For example, deep-ultraviolet (DUV) birefringent materials for light polarization are urgently needed for DUV lithography. Here we demonstrate based on computational and experimental results that parallel chains of corner-connected planar sp2-hybridized BO3 groups found in Ca(BO2)2 effectively produce large birefringence. Ca(BO2)2 achieves three vital "best" properties including the shortest UV cutoff edge, the largest birefringence, and the highest laser-induced damage threshold (LIDT) compared to all the reported borate birefringent materials. On the basis of a Ca(BO2)2 single crystal, a DUV Glan polarizer has been realized and is more efficient than one constructed with commercially available MgF2.

Spatial Analysis of Rice Blast in China at Three Different Scales.

In this study, spatial analyses were conducted at three different scales to better understand the epidemiology of rice blast, a major rice disease caused by Magnaporthe oryzae. At the regional scale, across the major rice production regions in China, rice blast incidence was monitored on 101 dates at 193 stations from 10 June to 10 September during 2009 to 2014, and surveyed in 143 fields in September 2016; at the county scale, three surveys were done covering one to five counties in 2015 to 2016; and, at the field scale, blast was evaluated in six fields in 2015 to 2016. Spatial cluster and hot spot analyses were conducted in the geographic information system on the geographical pattern of the disease at regional scale, and geostatistical analysis was performed at all three scales. Cluster and hot spot analyses revealed that high-disease areas were clustered in mountainous areas in China. Geostatistical analyses detected spatial dependence of blast incidence with influence ranges of 399 to 1,080 km at regional scale and 5 to 10 m at field scale but not at county scale. The spatial patterns at different scales might be determined by inherent properties of rice blast and environmental driving forces, and findings from this study provide helpful information to sampling and management of rice blast.

Functional Interactions Between Major Rice Blast Resistance Genes, Pi-ta and Pi-b, and Minor Blast Resistance Quantitative Trait Loci.

Major blast resistance (R) genes confer resistance in a gene-for-gene manner. However, little information is available on interactions between R genes. In this study, interactions between two rice blast R genes, Pi-ta and Pi-b, and other minor blast resistance quantitative trait loci (QTLs) were investigated in a recombinant inbred line (RIL) population comprising 243 RILs from a Cybonnet (CYBT) × Saber (SB) cross. CYBT has the R gene Pi-ta and SB has Pi-b. Ten differential isolates of four Magnaporthe oryzae races (IB-1, IB-17, IB-49, and IE-1K) were used to evaluate disease reactions of the 243 RILs under greenhouse conditions. Five resistance QTLs were mapped on chromosomes 2, 3, 8, 9, and 12 with a linkage map of 179 single nucleotide polymorphism markers. Among them, qBR12 (Q1), was mapped at the Pi-ta locus and accounted for 45.41% of phenotypic variation while qBR2 (Q2) was located at the Pi-b locus and accounted for 24.81% of disease reactions. The additive-by-additive epistatic interaction between Q1 (Pi-ta) and Q2 (Pi-b) was detected; they can enhance the disease resistance by an additive 0.93 using the 0 to 9 standard phenotyping method. These results suggest that Pi-ta interacts synergistically with Pi-b.

Transabdominal ultrasound-guided multifetal pregnancy reduction in 10 cases of monkeys.

Intracytoplasmic sperm injection (ICSI) and embryo transfer (ET) in nonhuman primates, e.g. rhesus and cynomolgus monkeys, has been widely used in researches of reproductive and developmental biology, and the success rate has been improved significantly. However, unwanted multiple pregnancy occurs frequently during the ICSI-ET in monkeys, most of which leads to miscarriages. To improve the birth rate of pregnancies and to safeguard health of host and baby monkeys, multifetal pregnancy reduction (MPR) is necessary. In this study, a total of 10 monkeys with multiple pregnancies received MPR through transabdominal ultrasound-guided potassium chloride injection into beating hearts of selective fetuses. To assess MPR efficiency, 31 monkeys with normal singleton pregnancies and 25 monkeys with twin pregnancies without MPR were used as controls. The aim of the reduction is to keep only one fetus, no matter twin or triplet pregnancy originally. Our results show that six cases of MPR were successful and all of them retained single fetus. Moreover, about 1 month (30.2 ± 1.2 days) of gestation is a better timing for MPR than later stage (50.7 ± 1.9 days). We also found that the remaining fetuses developed normally with full-term gestation and normal birth weight. In conclusion, transabdominal ultrasound-guided potassium chloride injection is a safe and effective MPR method for monkeys with multiple pregnancies.

Na2B6O9F2: A Fluoroborate with Short Cutoff Edge and Deep-Ultraviolet Birefringent Property Prepared by an Open High-Temperature Solution Method.

As important materials in modulating the polarization of light, birefringent crystals have attracted considerable attention and played crucial roles in the field of optical communication and the laser industry. Limited by the transparency range, few birefringent crystals can be used in the deep-ultraviolet (DUV) region, except for α-BaB2O4 (α-BBO). However, the application of α-BBO in the DUV range is restricted by the relatively high cutoff edge and low transmittance rate below 200 nm. In this paper, we design and synthesize a new fluoroborate, Na2B6O9F2, by introducing fluorine into borate system. It possesses a short cutoff edge of 169 nm and birefringence larger than 0.080 at 589.3 nm. The Na2B6O9F2 crystals with sizes up to 3.0 mm × 1.5 mm × 0.2 mm have been grown with good quality by a high-temperature solution method in the open system. First-principles calculations were carried out to understand the optical properties.