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An experimental investigation was conducted to evaluate the shear-friction capacity of cylindrical pocket connections without reinforcement crossing the interface, which is a common connection detail between precast concrete substructure elements. Current Code expressions for shear-friction capacity include components for cohesion or aggregate interlock and contribution from steel crossing the interface or a clamping force. These expressions were primarily derived and calibrated based on pushoff tests with reinforcement crossing the shear plane, which do not represent the behavior of the shear plane in a cylindrical pocket connection. Thirty-four large-scale specimens were built and tested to investigate the shear friction of the cylindrical pocket connection without reinforcing steel crossing the shear plane. This experimental study showed that current Code expressions provided conservative estimates for this connection. A revised proposed theory is presented that more accurately predicts the shear-friction capacity of this connection without interface steel.

There has been some recent debate about the actual behavior and performance of some components of strut-and-tie models, specifically struts. This research aims to shed additional light on the behavior and performance of struts. Five full-scale concrete deep beams with two different shapes (rectangular and truss-like) were tested under a three-point load setup. The shear span-to-effective depth ratio (a/d) for the specimens were 1 and 1.6, which led to strut angles of 30 and 45 degrees. All the specimens were simply supported vertically and reinforced with bonded or unbonded bars horizontally. The results indicate that the truss-like specimens have substantially more capacity compared to the rectangular specimens with similar dimension. The unbonded reinforced beam results were similar to bonded results. The ultimate shear strength obtained from the experimental tests was compared with strut-and-tie method (STM) estimates using current design codes to evaluate their safety and accuracy. Keywords: deep beams; failure mode; node behavior; strut-and-tie method; strut strength.

The effect of development type and length and beam geometry on the behavior of discontinuity regions in concrete deep beams was investigated through experimental testing and numerical study. Observations of cracking patterns and measurements of load and displacement at midspan of four large-scale concrete deep beams tested under a three-point load setup were used to calibrate numerical models. Thirty-five specimens were then modeled in a nonlinear finite element software to evaluate the strength of deep beams with different development lengths, development types, strut angles, and beam geometries. Development length and type of development was found to impact the presence of tensile stress in the support nodes. A rectangular beam geometry was found to cause diagonal tension stresses in the struts, not present in truss-like specimens. The tensile stresses from reinforcement development and diagonal tension were found to not be additive in these rectangular beams. Keywords: deep beam; development; failure mechanism; finite element; strut-and-tie.

Penile acquisition of HIV infection contributes substantially to the global epidemic. Our goal was to establish a preclinical macaque model of penile HIV infection for evaluating the efficacy of new HIV prevention modalities. Rhesus macaques were challenged once or twice weekly with consistent doses of SHIVsf162P3 (a chimeric simian-human immunodeficiency virus containing HIV env) ranging from 4-600 TCID50 (50% tissue culture infective dose), via two penile routes, until systemic SHIV infection was confirmed. One route exposed the inner foreskin, glans and urethral os to virus following deposition into the prepuce (foreskin) pouch. The second route introduced the virus non-traumatically into the distal urethra only. Single-route challenges resulted in dose-dependent rates of SHIV acquisition informing selection of optimal SHIV dosing. Concurrent SHIV challenges via the prepuce pouch (200 TCID50) and urethra (16 TCID50) resulted in infection of 100% (10/10) animals following a median of 2.5 virus exposures (range, 1-12). We describe the first rhesus macaque repeat-exposure SHIV challenge model of penile HIV acquisition. Utilization of the model should further our understanding of penile HIV infection and facilitate the development of new HIV prevention strategies for men.

Penile acquisition of HIV accounts for most infections among men globally. Nevertheless, candidate HIV interventions for men advance to clinical trials without preclinical efficacy data, due primarily to a paucity of relevant animal models of penile HIV infection. Using our recently developed macaque model, we show that a single subcutaneous administration of broadly neutralizing antibody (bNAb) 10-1074 conferred durable protection against repeated penile exposures to simian-human immunodeficiency virus (SHIV SF162P3 ). Macaques co-administered bNAbs 10-1074 and 3BNC117, or 3BNC117 alone, also exhibited significant protection against repeated vaginal SHIV AD8-EO exposures. Regression modeling estimated that individual plasma bNAb concentrations of 5 μg ml −1 correlated with ≥99.9% relative reduction in SHIV infection probability via penile (10-1074) or vaginal (10-1074 or 3BNC117) challenge routes. These results demonstrate that comparably large reductions in penile and vaginal SHIV infection risk among macaques were achieved at clinically relevant plasma bNAb concentrations and inform dose selection for the development of bNAbs as long-acting pre-exposure prophylaxis candidates for use by men and women. Here, using a repeat-exposure penile SHIV infection model in macaques, the authors show that a single subcutaneous administration of a broadly neutralizing antibody (bNAb) exerts long-acting protection against both penile and vaginal virus exposure, which highlights bNAbs as a potential therapeutic for LA-PrEP.

Conventional driven piles are made from steel, concrete, timber, or composite materials. These piling options have limitations with respect to corrosion, durability, driveablity, and performance. Ultra-High-Performance Concrete (UHPC) pile is a new alternative that has already been adopted by various state Departments of Transportation in the United States for addressing the limitations that exist with conventional piles. UHPC piles are made of a cementitious composite material mixture that possesses exceptional properties such as higher strength, low capillary porosity, and high resistance to corrosion, making them a suitable option for use as a deep foundation. For several reasons, it is necessary to cast piles with a shorter length and splice them at the site to reach the desired lengths. These reasons include shipping limitations, unpredictable soil condition, reducing transportation costs, construction time, and damage during installation. This study aims to explore and summarize the currently available options for connecting UHPC pile segments. Accordingly, after a brief introduction on driven piles, this paper investigates various splicing systems that can be used for UHPC piles through reviewing previous research studies and field applications. The applicable splices are then compared based on several criteria such as capacity, durability, cost, and ease of application.

Solomon’s sea (a brass basin used in the First Temple) was discussed in the Yerushalmi Talmud Eruvin 1:5 (as well as in BT Eruvin 14a-b), and it revolved around the shape of Solomon’s sea. However, inaccurate volume values of the basin were cited in the Yerushalmi. The aim of this article was to offer a new explanation for one problem arising in connection with these values. The setting of this study was the inaccurate volume values of the basin appearing in the Yerushalmi. The background of the issue at stake is the fact that Jewish scholars cannot accept that Scripture contains discrepancies (cf. BerR. 4:6). Our methods were to review the different explanations given by different commentators and to introduce a discussion by R. Avraham Ben Hiyya ha-Nassi and the Book of Tashbetz dealing with an explanation of verses related to the basin’s shape. We suggested a new idea based on the above-mentioned discussion: by reducing the basin’s width by one handbreadth as the verse states, one could reach exactly the values appearing in the Yerushalmi for the volumes of a squared basin and a circular basin. Based on our suggestion, one could settle the volume values appearing in the Yerushalmi without correcting them.Contribution: The key insight was that one could settle the volume values appearing in the Yerushalmi without correcting them. This insight was connected with the textual history of the Rabbinic literature, which exactly fit HTS’s scope.

Windisch explores the study by Klein et al about strut strength and failure in full-scale concrete deep beams. He cites how the authors praise the strut-and-tie method (STM) as \"one of the most universally applicable methods to design a concrete structure,\" which is not the case--STMs for opening corners and dapped ends are missing until today. He is also critical to the conclusions of the study where authors refer to the test results of Pujol et al. as a verification of their results. Pujol's conclusions are valid to all inclinations of struts. Moreover, they obey the fundamental principle of theory of plasticity: when adding weightless and load-bearing material to the strut (bottle), the load-bearing capacity of the strut will not be less.

Pile splicing is generally considered in construction because of transportation limits, length requirements, construction means and methods, and strength capacity. A major challenge in the use of precast prestressed UHPC piles is the lack of efficient and effective splicing solutions. To address the problem, this study evaluated different pile splicing methods for UHPC H-piles and their constructability. The analysis and design for strength capacity and detailing presented here are based on relevant established guidelines and design codes for UHPC. This study assessed two pile splicing methods: epoxy-bonded dowels and near-surface mounted bars (NSMBs). The analysis demonstrated that the epoxy-bonded dowel method provides a moment capacity that is 127% of the pile moment capacity in the strong direction and 139% of the pile moment capacity in the weak direction. In comparison, the NSMB method achieved 121% in the strong direction and 106% in the weak direction. Both methods developed the established strength capacity requirements. The constructability of both pile splicing options was evaluated to provide practical guidelines for their preparation in preplanned and unplanned situations. The results reported are for 18-inch UHPC H-piles; however, the construction and analytical approach applies to other pile sizes as well. The pile splicing options developed are recommended for further experimental investigations.

Natural-product derived lectins can function as potent viral inhibitors with minimal toxicity as shown in vitro and in small animal models. We here assessed the effect of rectal application of an anti-HIV lectin-based microbicide Q-Griffithsin (Q-GRFT) in rectal tissue samples from rhesus macaques. E-cadherin + cells, CD4 + cells and total mucosal cells were assessed using in situ staining combined with a novel customized digital image analysis platform. Variations in cell numbers between baseline, placebo and Q-GRFT treated samples were analyzed using random intercept linear mixed effect models. The frequencies of rectal E-cadherin + cells remained stable despite multiple tissue samplings and Q-GRFT gel (0.1%, 0.3% and 1%, respectively) treatment. Whereas single dose application of Q-GRFT did not affect the frequencies of rectal CD4 + cells, multi-dose Q-GRFT caused a small, but significant increase of the frequencies of intra-epithelial CD4 + cells (placebo: median 4%; 1% Q-GRFT: median 7%) and of the CD4 + lamina propria cells (placebo: median 30%; 0.1–1% Q-GRFT: median 36–39%). The resting time between sampling points were further associated with minor changes in the total and CD4 + rectal mucosal cell levels. The results add to general knowledge of in vivo evaluation of anti-HIV microbicide application concerning cellular effects in rectal mucosa.