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【Objective】 Straw mulching and ridge tillage is an improved agronomic technology to sustain crop production in the loess plateau in northwestern China. How their combination impacts water uptake and crop yield is not well understood. This paper is to fill this knowledge gap. 【Method】 The experiment was conducted in a potato field and compared ridge tillage and traditional flatten tillage. For the ridge tillage, there were three mulching treatments: film mulching (PM), locally high straw mulching (RSM9), and locally low straw mulching (RSM6). For the traditional flatten tillage, there were also three treatments: locally high straw mulching (PSM9), locally low straw mulching (PSM6), and full straw mulching (FC). The control is flatten tillage without mulching. 【Result】 ①Compared with CK, mulching increased the yield and WUE of the potato by 11.8%~21.7% and 15.9%~26.7%, respectively. Compared with PSM treatments, RSM treatments increased the yield and WUE of the potato by 1.5% and 1.7%, respectively. Compared with the locally high straw mulching (9 000 kg/hm2), the locally low straw mulching (6 000 kg/hm2) increased the yield and WUE by 6.1% and 6.5%, respectively. ② Compared with CK, local straw mulching increased soil moisture in some regions and reduced it in other regions, but overall, it increased soil water content. The increased soil water storage under different treatments was ranked in the order of RSM6 >PSM6 >RSM9 >PSM9 treatment. ③ Compared with CK, partial straw mulching increased total water consumption, daily water consumption, and water consumption coefficient for potato tuber formation and starch accumulation by 4.6 mm, 0.11 mm/d and 2.7%, respectively. Water consumption during tuber expansion and harvest was greater in RSM than in PSM, while the opposite was true during soil-tuber expansion. 【Conclusion】 Straw mulching can reduce water consumption before tuber expansion, increase water consumption after tuber expansion, balance water consumption and demand during key growth stages, and promote potato growth and development. For all treatments we compared, ridge tillage coupled with partial straw mulching at 6 000 kg/hm2 was most effective.

Objective To explore the effect of hypoxia inducible factor 1α (HIF⁃1α) gene silencing in rat bone mar⁃ row mesenchymal stem cells (BMMSCs) under mechanical distraction on the expression of bone sialoprotein (BSP) and osterix and to provide a new idea for repairing bone defects with BMMSCs. Methods The shRNA sequence was de⁃signed according to the rat HIF⁃1α gene, and the pGMLV⁃SC1RNAi lentiviral vector was cloned after PCR amplifica⁃ tion. After screening positive clones and identifying competent transformed cells by sequencing, 293T cells were pack⁃ aged and titered, rat BMMSCs were transfected and cultured in vitro. Clones with stably silenced HIF⁃1α expression were screened by inverted fluorescence microscopy. The RNAi response experiment was divided into four groups: the blank control group, the HIF⁃1α shRNA group, the negative control group, and the response group. Western blot was used to detect the expression of HIF⁃1α protein in the four groups to verify the response of the target genes and exclude off⁃target effects. A Flexcell FX⁃5000T cell stress loading system was used to intervene in the mechanical stretch of the cells. qRT⁃PCR and Western blot were used to detect the expression of BSP and osterix in the blank control group, HIF⁃ 1α shRNA group, and negative control group. Results The HIF ⁃ 1α shRNA lentiviral vector was successfully con⁃ structed. The results of the RNAi response showed no significant difference in the expression of HIF⁃1α between the re⁃ sponse and the blank control group (P > 0.05). The recombinant lentivirus could effectively silence HIF ⁃ 1α in BMMSCs. After mechanical distraction of the BMMSCs, compared with the blank and negative control groups, the HIF⁃ 1α shRNA group showed significantly increased mRNA and protein expression of the bone⁃related factors BSP and os⁃ terix (P < 0.05); there was no significant difference in the mRNA and protein expression of BSP or osterix between the blank and negative control groups (P > 0.05). Conclusion Silencing HIF⁃1α in BMMSCs under mechanical distrac⁃ tion can promote the expression of BSP and osterix.

Donor–acceptor Stenhouse adducts (DASA) have recently emerged as a class of visible-light-induced photochromic molecular switches, but their photocyclization mechanism remains puzzling and incomplete. In this work, we carried out MS-CASPT2//SA-CASSCF calculations to reveal the complete mechanism of the dominant channels and possible side reactions. We found that a new thermal-then-photo isomerization channel, i.e., EEZ → EZZ → EZE , other than the commonly accepted EEZ → EEE → EZE channel, is dominant in the initial step. Besides, our calculations rationalized why the expected byproducts ZEZ and ZEE are unobserved and proposed a competitive stepwise channel for the final ring-closure step. The findings here redraw the mechanistic picture of the DASA reaction by better accounting for experimental observations, and more importantly, provide critical physical insight in understanding the interplay between thermal- and photo-induced processes widely present in photochemical synthesis and reactions. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the efficacy of customized allogeneic bone block (CABB) for ridge augmentation compared with autogenous bone block. Materials and Methods: Patients (N = 24) in need of ridge augmentation were randomly assigned to one of two treatment modalities: CABBs (CABB group) and autogenous bone blocks (ABB group). The primary outcome of the present study was the horizontal bone gain at 1 mm below the alveolar ridge crest (HBG1). Secondary outcomes were the bone gain at other levels, bone resorption rate, ridge width, operative time, postoperative pain score, and histological results. The data obtained from the current study were analysed using a generalized linear mixed effects model, two‐sample t‐test, or a Mann–Whitney U‐test. Results: Twenty‐four patients completed a 6‐month follow‐up. One patient in the CABB group exhibited block exposure. The CABB group had significantly more horizontal bone gain (HBG1) and less horizontal bone resorption (HBRR1) at 1 mm below the alveolar ridge crest when compared with those in the ABB group (HBG1: CABB group [4.29 ± 1.48 mm] and ABB group [1.12 ± 3.25 mm]; HBRR0: CABB group [42.15 ± 14.03%] and ABB group [92.52 ± 55.78%], p <.05). In addition, a longer operative time was reported in the ABB group compared with the CABB group (p <.05). The histological observation indicated a new bone formation in both groups. Conclusions: The use of CABBs resulted in more horizontal bone gain and less horizontal bone resorption at 1 mm below the alveolar ridge crest at 6 months post‐surgery compared with ABBs while reducing the operative time in the treatment of ridge augmentation. [ABSTRACT FROM AUTHOR]