Pengaruh Bagian Kayu dan Ketebalan Stiker pada Pengeringan Alami terhadap Sifat Fisika Kayu Gerunggang (Cratoxylon arborescens Bl.)

The existence of the wood needs to be considered so that the use of wood for a particular use needs to pay attention to the quality of wood, both for wood for building materials, furniture, panels, crafts and so on. The weakness of wood compared to substitutes such as metal and concrete is its hygroscopic nature. The aim of this study was to determinethe effect of wood parts treatment on axial direction and sticker thickness on natural drying time on changes in the physical properties of gerunggang wood (Cratoxylon arborescens Bl.). While the expected benefits are as information material for the wood processing industry and wood users to be able to dry the wood properly. The research was conducted at the Forest Products Technology Laboratory for 3 months. Cutting is done by dividing the length of the stem into 3 (three) equal parts in the axial position, namely the base (a1), middle (a2) and end (a3), each cut length ± 2 m for the board (example drying test) ) with ± 2 cm thick and ± 15 cm long for example test of moisture content, specific gravity and shrinkage. The results showed that the average value of fresh water content, saturated point moisture content, and air dry water content had a tendency to decrease in value from the base to the end of the stem. The natural dryingtime has an average tendency to dry more quickly from the base to the end of the stem, with drying times ranging from 28-40 days or an average of 33 days. The end of the wood with a thickness of 3,5 cm sticker dries faster (25 days) with a defect 1 broken edge. Parts of wood with a sticker thickness of 3,5 cm dries faster than the thickness of the stickers 2,5 cm and 1,5 cm. The results of measurements of (BJ) density of gerunggang wood averaged 0,55 including the medium group (BJ 0,4-0,6). Specific gravity has a tendency to increase in value from the base to the end of the rod with an uneven pattern including type 3. The tangential and radial direction shrinkage ratio of 1,88 is included in the medium classification, then gerunggang wood can be used for boards and lightweight construction under the roof, crates, furniture, plywood andconcrete molds. It is recommended to conduct further research on the possibility of using gerunggang wood for artificial boards.Keywords: drying, wood parts, physical properties, gerunggang

Social preferences, accountability, and wage bargaining

We assess the extent of preferences for employment in a collective wage bargaining situation with heterogeneous workers. We vary the size of the union and introduce a treatment mechanism transforming the voting game into an individual allocation task. Our results show that highly productive workers do not take employment of low productive workers into account when making wage proposals, regardless of whether insiders determine the wage or all workers. The level of pro-social preferences is small in the voting game, while it increases as the game is transformed into an individual allocation task. We interpret this as an accountability effect

Modeling the mitochondrial cardiomyopathy of Barth syndrome with iPSC and heart-on-chip technologies

Studying monogenic mitochondrial cardiomyopathies may yield insights into mitochondrial roles in cardiac development and disease. Here, we combine patient-derived and genetically engineered iPSCs with tissue engineering to elucidate the pathophysiology underlying the cardiomyopathy of Barth syndrome (BTHS), a mitochondrial disorder caused by mutation of the gene Tafazzin (TAZ). Using BTHS iPSC-derived cardiomyocytes (iPSC-CMs), we defined metabolic, structural, and functional abnormalities associated with TAZ mutation. BTHS iPSC-CMs assembled sparse and irregular sarcomeres, and engineered BTHS “heart on chip” tissues contracted weakly. Gene replacement and genome editing demonstrated that TAZ mutation is necessary and sufficient for these phenotypes. Sarcomere assembly and myocardial contraction abnormalities occurred in the context of normal whole cell ATP levels. Excess levels of reactive oxygen species mechanistically linked TAZ mutation to impaired cardiomyocyte function. Our study provides new insights into the pathogenesis of Barth syndrome, suggests new treatment strategies, and advances iPSC-based in vitro modeling of cardiomyopathy

CAS9 transcriptional activators for target specificity screening and paired nickases for cooperative genome engineering

Prokaryotic type II CRISPR-Cas systems can be adapted to enable targeted genome modifications across a range of eukaryotes.1–7. Here we engineer this system to enable RNA-guided genome regulation in human cells by tethering transcriptional activation domains either directly to a nuclease-null Cas9 protein or to an aptamer-modified single guide RNA (sgRNA). Using this functionality we developed a novel transcriptional activation–based assay to determine the landscape of off-target binding of sgRNA:Cas9 complexes and compared it with the off-target activity of transcription activator–like (TAL) effector proteins8, 9. Our results reveal that specificity profiles are sgRNA dependent, and that sgRNA:Cas9 complexes and 18-mer TAL effector proteins can potentially tolerate 1–3 and 1–2 target mismatches, respectively. By engineering a requirement for cooperativity through offset nicking for genome editing or through multiple synergistic sgRNAs for robust transcriptional activation, we suggest methods to mitigate off-target phenomena. Our results expand the versatility of the sgRNA:Cas9 tool and highlight the critical need to engineer improved specificity

On the Determinants of Currency Crises: The Role of Model Uncertainty

We tackle explicitly the issue of model uncertainty in the framework of binary variable models of currency crises. Using Bayesian model averaging techniques, we assess the robustness of the explanatory variables proposed in the recent literature for both static and dynamic models. Our results indicate that the variables belonging to the set of macroeconomic fundamentals proposed by the literature are very fragile determinants of the occurrence of currency crises. The results improve if the crisis index identifies a crisis period (defined as the period up to a year before a crisis) instead of a crisis occurrence. In this setting, the extent of real exchange rate misalignment and financial market indicators appear as robust determinants of crisis periods