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Liquid crystalline elastomers (LCEs) are crosslinked polymer networks that combine the elastic properties of rubber with the anisotropic properties of liquid crystals. Multifunctionality and responsivity can be programmed into LCEs by patterning their local orientation, which is difficult to achieve in other monolithic material systems. Advances in the synthesis and alignment of LCEs have paved the way for their functional integration in robotics, optics, consumer products, energy and healthcare devices. In this Review, we discuss recent advances in materials chemistry and processing that have contributed to the resurgence in LCE research. We examine the mechanical response of LCEs to stimuli and survey approaches for mechanical alignment, surface-enforced alignment, field-induced alignment and rheological alignment. The Review concludes with an over-the-horizon outlook discussing current challenges and emerging research opportunities. Liquid crystalline elastomers are stimuli-responsive polymeric materials whose mechanical properties can be programmed by patterning their local orientation, making them promising candidates to serve as low-density actuators and functional elements in various applications. This Review discusses the synthesis and processing of liquid crystalline elastomers, with a focus on alignment methods and potential applications.

A total of 710 pigs (Line 400 × 200, DNA, Columbus, net energy (NE)) were used in two experiments (Exp. 1: initially, 6.3 ± 0.05 kg; Exp. 2: initially, 6.8 ± 0.05 kg) to evaluate the effects of two medium-chain fatty acid (MCFA) based products on nursery pig growth performance. Following their arrival at the nursery facility, pigs were randomized to pens (five pigs per pen) and allowed a 4-d acclimation period. Thereafter, pens of pigs were blocked by initial weight and randomized to dietary treatment. In Exp. 1, the dietary treatments were a dose titration of: 0%, 0.5%, 1.0%, or 2.0% MCFA-based additive, as well as a diet including 1.0% MCFA from a 1:1:1 blend of C6:0, C8:0, and C10:0. In Exp.2, dietary treatments consisted of a basal diet containing no MCFA (control), the control diet with a 1.0% inclusion of four different blends of MCFA, lactic acid, and monolaurin or a diet with 1.0% added MCFA (a 1:1:1 blend of C6:0, C8:0, and C10:0). The four blends consisted of 50% C6:0, 20% lactic acid, and increasing levels of monolaurin (0%, 10%, 20%, and 30%) at the expense of C12:0 (30%, 20%, 10%, and 0%). Treatment diets were formulated and manufactured in two dietary phases. Data were analyzed as a randomized complete block design with pen as the experimental unit. In Exp. 1, overall (days 0–34), increasing CaptiSURE increased (linear, P ≤ 0.014) average daily gain (ADG) and average daily feed intake (ADFI). Feed efficiency improved (quadratic, P = 0.002) with increasing CaptiSURE up to 1.0% of the diet with no benefit thereafter. There was no evidence for differences between pigs fed 1.0% CaptiSURE and pigs fed the 1.0% MCFA blend of C6:0, C8:0, and C10:0. In Exp. 2, overall (days 0–35), pigs fed the 1.0% 1:1:1 MCFA blend had increased (P < 0.034) ADFI and ADG resulting in 0.9 kg greater final weight (P = 0.014) compared with the control group. There was no evidence that the mean performance of pigs fed the four blends of MCFA, lactic acid, and monolaurin were different from the pigs fed the control diet. In summary, the addition of a 1.0% 1:1:1 blend of C6:0, C8:0, and C10:0 in nursery pig diets improved ADG, ADFI, and gain to feed ratio (G:F) compared with pigs fed the control diet. In addition, providing nursery pigs with the MCFA product CaptiSURE, up to 2% of the diet, resulted in linear improvements in ADG and ADFI. Altering the C12:0 to monolaurin ratio and adding lactic acid did not improve growth performance compared with pigs fed the control diet.

A total of 140 weanling pigs (241 × 600, DNA, Columbus, NE; initially 5.5 ± 0.79 kg body weight) were used in a 32-d study evaluating the effects of increasing dietary Fe from either iron sulfate (FeSO4) or iron carbonate (FeCO3) on nursery pig growth performance and blood Fe status. The pigs used for this trial did not receive an Fe injection after birth in order to increase the sensitivity to added dietary Fe after weaning. Pigs were weaned at approximately 21 d and allotted to pens based on the initial weight in a completely randomized block design with five pigs in each pen and four pens per treatment. Experimental treatments were arranged as a 2 × 3 + 1 factorial with main effects of dietary Fe source (FeSO4 vs. FeCO3) and level (10, 30, or 50 mg/kg of added Fe) plus a negative control with no additional dietary Fe. The basal diet contained 40 mg/kg total dietary Fe based on ingredient contributions and was formulated with an Fe-free trace mineral premix. Experimental diets were formulated below the pigs recommended Fe requirement based on NRC (2012) estimates. Experimental diets were fed in pellet form in a single phase for the duration of the trial. From day 0 to 32, there was no evidence for source × level interactions for growth performance, hemoglobin (Hb), or hematocrit (Hct) values. There was no evidence for a difference (P > 0.10) in dietary Fe source. Providing increasing Fe levels in the diet from either FeSO4 or FeCO3 improved (P < 0.05) average daily gain, average daily feed intake, gain-to-feed ratio, and increased (P < 0.05) Hb and Hct values. A day effect (P = 0.001) was observed for both Hb and Hct with values increasing throughout the study. Increasing dietary Fe levels in the diet from either FeSO4 or FeCO3 increased (linear; P < 0.05) Hb and Hct values on days 14, 21, and 32. In summary, these data suggest that the micronized form of FeCO3 is a source of Fe that can be added to nursery diets to yield similar responses to those observed from FeSO4 supplementation. Similar to previous research, increasing dietary Fe improved the growth performance and increased Hb and Hct values when pigs have low Fe status at weaning.

A total of 336 newborn pigs (DNA 241 × 600, initially 1.75 ± 0.05 kg bodyweight [BW]) from 28 litters were used in a 63-d study evaluating the effects of increasing injectable Fe dose on suckling and subsequent nursery pig performance and blood Fe status. GleptoForte (Ceva Animal Health, LLC, Lenexa, KS) contains gleptoferron which is an Fe macromolecule complex that is commercially used as an injectable Fe source for suckling piglets. On the day of processing (day 3 after birth), all piglets were weighed and 6 barrows and 6 gilts per litter were allotted within sex to 1 of 6 treatments in a completely randomized design. Treatments consisted of a negative control receiving no Fe injection and increasing injectable Fe to achieve either 50, 100, 150, 200 mg, or 200 mg plus a 100 mg injection on day 11 after birth. Pigs were weaned (~21 d of age) and allotted to nursery pens based on BW and corresponding treatment in a completely randomized design. During lactation, increasing injectable Fe up to 100 mg improved (quadratic; P < 0.05) average daily gain (ADG) and day 21 BW with no further improvement thereafter. There was no evidence of differences (P > 0.10) observed between the 200 mg and 200 mg + 100 mg treatments for growth. For the nursery period, increasing Fe dosage increased (linear; P < 0.05) ADG, average daily feed intake, and day 42 BW. There was no evidence of differences (P > 0.10) between the 200 mg and 200 mg + 100 mg treatments for nursery growth. For blood criteria, significant treatment × day interactions (P = 0.001) were observed for hemoglobin (Hb) and hematocrit (Hct). The interactions occurred because pigs that had

Three studies evaluated the effects of added dietary salt on growth performance of pigs weighing 7 to 10, 11 to 30, and 27 to 65 kg. In experiment 1, 325 pigs were used with 5 pigs per pen and 13 pens per treatment. Pigs were fed a diet (0.39% Na and 0.78% Cl) for 7 d after weaning, then randomly assigned to diets with either 0, 0.20, 0.40, 0.60, or 0.80% added salt for 14 d. All diets were corn-soybean meal-based with 10% dried whey. Calculated Na concentrations were 0.11, 0.19, 0.27, 0.35, and 0.43% and calculated Cl concentrations were 0.23, 0.35, 0.47, 0.59, and 0.70%, respectively. Increasing salt increased (linear, P < 0.05) average daily gain (ADG) and gain to feed ratio (G:F). For ADG, the linear, quadratic polynomial (QP), and broken-line linear (BLL) models were competing with the breakpoint for the BLL at 0.59% salt. For G:F, the BLL reported a breakpoint at 0.33% while the QP indicated maximum G:F at 0.67% added salt. In experiment 2, 300 pigs were used in a 34-d trial with 5 pigs per pen and 12 pens per treatment. Pigs were weaned at 21 d of age and fed a phase 1 diet (0.50% Na and 0.67% Cl) for 11 d and then a phase 2 diet (0.35% Na and 0.59% Cl) for 14 d. Then pens of pigs were randomly assigned to corn-soybean meal-based diets containing 0.20, 0.35, 0.50, 0.65, or 0.80% added salt. Calculated dietary Na concentration were 0.10, 0.16, 0.22, 0.28, and 0.34% and calculated Cl concentrations were 0.23, 0.32, 0.41, 0.50, and 0.59%, respectively. Overall, ADG and G:F increased (quadratic, P < 0.07) with increasing added salt. For ADG, the QP and BLL had similar fit with the breakpoint for BLL at 0.51% added salt. For G:F, the BLL model predicted a break point at 0.35% added salt. In experiment 3, 1,188 pigs were used in a 44-d study with 27 pigs per pen and 11 pens per treatment. Pens of pigs were randomly assigned to corn-soybean meal-based diets containing 0.10, 0.33, 0.55, or 0.75% added salt. Calculated dietary Na concentrations were 0.10, 0.19, 0.28, and 0.36% and calculated Cl concentrations were 0.23, 0.36, 0.49, and 0.61%, respectively. Overall, there was no evidence to indicate that added salt above 0.10% of the diet affected growth. In conclusion, the BLL models suggested to maximize ADG for 7 to 10 and 11 to 30 kg pigs was 0.59% (0.34% Na and 0.58% Cl) and 0.51% added salt (0.22% Na and 0.42% Cl), respectively. There was no evidence that growth of 27 to 65 kg pigs was improved beyond 0.10% added salt (0.11% Na and 0.26% Cl).

Recent research has reported that increasing standardized ileal digestible (SID) Trp:Lys ratio above 20% in finishing pigs fed Ractopamine HCL (RAC) resulted in improved growth and carcass performance, however this response has been inconsistent. Therefore, the objective of this study was to evaluate the effects of feeding high SID Trp:Lys ratios with RAC on growth and carcass performance. A total of 1,791 finishing pigs (PIC 1050×337; initially 110 kg BW) were used in a 27-d study. Pens of 25 or 26 pigs were allotted by initial BW and randomly assigned to 1 of 5 dietary treatments in a RCBD with 14 replications per treatment. The dietary treatments consisted of 5 SID Trp:Lys ratios (20, 22, 24, 26, and 28%). Corn-soybean meal-based diets were formulated to 0.90% SID Lys and contained 10 ppm ractopamine. At d 27, pigs were transported to a packing plant for processing and carcass data collection. Growth data were analyzed (GLIMMIX procedure of SAS) as a RCBD with pen as the experimental unit and initial BW as a covariate. Carcass data were analyzed with pen as the experimental unit and block × treatment as the random effect. Hot carcass weight served as a covariate for analysis of backfat, loin depth, and lean percentage. For overall growth performance, increasing SID Trp:Lys increased (linear, P< 0.0001) SID Trp g/kg of gain and SID Trp intake (Table 1); however, there were no evidence of treatment differences (P >0.10) for ADG or G:F. For carcass characteristics, increasing SID Trp:Lys decreased (linear; P=0.002) carcass yield and tended to decrease (P=0.078) lean percentage. There was no evidence of treatment differences (P >0.10) for HCW, loin depth, carcass ADG, or carcass feed efficiency. In summary, increasing SID Trp:Lys ratios above 20% in pigs fed RAC did not improve growth or carcass performance.

A total of 350 pigs (DNA 400×200, initial BW=6.3 kg) were used in a 34-d growth trial to evaluate the effects of a medium chain fatty acid (MCFA)-based feed additive in nursery pig diets. Following arrival to the nursery facility, pigs were randomized to pens (5 pigs per pen) and allowed a 4-d acclimation period. Thereafter, pens of pigs were blocked by BW and randomized to 1 of 5 dietary treatments (14 pens per treatment). Treatments were a dose response of 0, 0.5, 1.0, or 2.0% MCFA-based additive (CaptiSURE, Kemin Industries, Inc.; Des Moines, IA) as well as a treatment including 1.0% MCFA from a 1:1:1 blend of C6, C8, and C10 (Sigma Aldrich, St. Louis, MO). Treatment diets were formulated and manufactured in two dietary phases (d 0 to 13 and 13 to 34). Data were analyzed as a randomized complete block design with pen serving as the experimental unit. Overall (d 0 to 34), increasing CaptiSURE increased (linear, P ≤ 0.014) ADG and ADFI. Feed efficiency improved (quadratic, P = 0.002) with increasing CaptiSURE up to 1% of the diet with no benefit thereafter. As a result of the linear improvement in ADG, pigs fed 2.0% CaptiSURE were 1.8 kg heavier (P = 0.05) than pigs fed diets without MCFA at d 34. There was no evidence for differences between pigs fed 1.0% CaptiSURE and pigs fed the 1.0% MCFA blend of C6, C8, and C10 in phase 1, phase 2 or in overall performance. In summary, the addition of up to 2% of this MCFA-based additive in nursery pig diets resulted in linear improvements in ADG and ADFI. The MCFA-based feed additive also resulted in a similar improvement in growth performance as the C6, C8, and C10 MCFA blend when both were added at 1% of the diet.

A total of 2,673 mixed sex pigs (DNA 600 × PIC 1050; initially 21.4 kg BW) were used in a 117-d study to evaluate the effects of increasing SID Lysine:Calorie NE ratio on the growth performance and carcass characteristics of DNA sired pigs. Pens of pigs (30 pigs/pen) were blocked by BW and location and allotted to 1 of 4 dietary treatments with 18 pens per treatment. Treatments were 90%, 95%, 100%, or 105% of the 2016 PIC recommended SID Lysine:Calorie NE ratio for finishing gilts. Data were analyzed as a randomized complete-block design with pen as the experimental unit. Overall (d 0-117), increasing Lysine:Calorie NE tended to improve ADG (Linear; P = 0.077) and G:F (Linear; P = 0.053). Although there was an increase in ADG with increasing SID Lysine:Calorie NE, there was no evidence for a difference (P > 0.100) in final BW. The lack of BW response is most likely due to the lower (Quadratic; P < 0.008) removal rate as SID Lysine:Calorie NE increased. Carcass ADG (Linear; P < 0.064) tended to improve as SID Lysine: Calorie NE increased. An improvement in carcass G:F (Quadratic; P < 0.004) was observed as SID Lysine:Calorie NE increased to 100% PIC (2016) recommendations, with little improvement observed thereafter. No significant differences were observed in carcass yield, loin depth, back fat, or % lean. These results suggests that DNA sired pigs fed increasing SID Lysine:Calorie NE ratios tended to have improved growth performance with no impact on carcass quality.

Phytases are important commercial enzymes that catalyze the dephosphorylation of myo-inositol hexakisphosphate (phytate) to its lower inositol phosphate (IP) esters, IP6 to IP1. Digestion of phytate by Citrobacter braakii 6-phytase deviates significantly from monophasic Michaelis-Menten kinetics. Analysis of phytate digestion using isothermal titration calorimetry (ITC) using the single injection method produced a thermogram with two peaks consistent with two periods of high enzyme activity. Continuous-flow electrospray ionization time-of-flight mass spectroscopy (ESI-ToF-MS) provided real-time analysis of phytase catalysis. It was able to show that the first two cleavage steps were rapid and concurrent but the third cleavage step from IP4 to IP3 was slow. The third (IP4 to IP3), fourth (IP3 to IP2) and fifth (IP2 to IP1) cleavages were effectively sequential due to the preferred association of the more phosphorylated species with the phytase catalytic site. This created a bottleneck during the cleavage of IP4 to IP3 until the point at which IP4 was exhausted and was followed by the rapid cleavage of IP3 to IP2, which was observed as the second peak in the ITC thermogram. This work illustrates the importance of an orthogonal approach when studying non-specific or complex enzyme catalyzed reactions.

Formaldehyde-based feed additives are approved in the US for Salmonella control and reducing bacterial contamination in animal feed. However, we hypothesize formaldehyde inclusion in swine diets may influence gut microbial composition due to its antimicrobial properties which might negatively influence microbial populations and pig growth performance. Also, formaldehyde inclusion in diets is known to reduce the dietary availability of amino acids. Therefore, our study was conducted to characterize if the effects of feed formaldehyde-treatment are due to influences on microbial population or diet amino acid (AA) sources. Dietary treatments were arranged in a (2 × 2) + 1 factorial with formaldehyde treatment (none vs. 1000 ppm formaldehyde) and crystalline AA inclusion (low vs. high) with deficient AA content plus a positive control diet to contain adequate AA content without dietary formaldehyde. Treating diets with formaldehyde reduced growth rate (P = 0.001) while the AA inclusion had no evidence of impact. Formaldehyde reduced feed bacterial content and altered fecal microbial communities (P

Hindbrain glucagon-like peptide 1 (GLP-1) neurons project to numerous forebrain areas, including the lateral septum (LS). Using a fluorescently labeled GLP-1 receptor (GLP-1R) agonist, Exendin 4 (Ex4), we demonstrated GLP-1 receptor binding throughout the rat LS. We examined the feeding effects of Ex4 and the GLP-1R antagonist Exendin (9–39) (Ex9) at doses subthreshold for effect when delivered to the lateral ventricle. Intra-LS Ex4 suppressed overnight chow and high-fat diet (HFD) intake, and Ex9 increased chow and HFD intake relative to vehicle. During 2-h tests, intra-LS Ex9 significantly increased 0.25 M sucrose and 4% corn oil. Ex4 can cause nausea, but intra-LS administration of Ex4 did not induce pica. Furthermore, intra-LS Ex4 had no effect on anxiety-like behavior in the elevated plus maze. We investigated the role of LS GLP-1R in motivation for food by examining operant responding for sucrose on a progressive ratio (PR) schedule, with and without a nutrient preload to maximize GLP-1 neuron activation. The preload strongly suppressed PR responding, but blockade of GLP-1R in the intermediate subdivision of the LS did not affect motivation for sucrose under either load condition. The ability of the nutrient load to suppress subsequent chow intake was significantly attenuated by intermediate LS Ex9 treatment. By contrast, blockade of GLP-1R in the dorsal subdivision of the LS increased both PR responding and overnight chow intake. Together, these studies suggest that endogenous activity of GLP-1R in the LS influence feeding, and dLS GLP-1Rs, in particular, play a role in motivation.

To bring GAL4 production under the control of the sex promoter (P1) contained within Drosophila's fruitless gene, a gal4 cassette was previously inserted downstream of P1. This insert should eliminate male-specific FRU(M) proteins, which normally contain 101 amino acids (aa's) at their N termini. Thus males homozygous for the P1-gal4 insert should be courtless, as was briefly stated to be so in the initial report of this transgenic type. But XY flies whose only fru form is P1-gal4 have now been found to court vigorously. P1-gal4 females displayed no appreciable male-like actions except courtship rejection behaviors; yet, they developed a male-specific abdominal muscle. No immunoreactivity against the male-specific aa's was detectable in P1-gal4 flies. But male-like neural signals were observed in XY or XX P1-gal4 pupae and adults after applying an antibody that detects all FRU isoforms; transgenic females displayed reduced expression of such proteins. RT-PCR's rationalized these findings: P1 transcripts include anomalous splice forms from which gal4 was removed, allowing FRU's lacking M aa's to be produced in male-like patterns in both sexes. Within males, such defective proteins promote neural differentiation and function that is sufficient to support spirited P1-gal4 courtship. But dispensability of the male-specific FRU N-terminus is tempered by the finding that intra-fru sequences encoding these 101 aa's are highly conserved among interspecific relatives of D. melanogaster.

The reactions of Ln(NO(3))(3) (Ln = La, Er) with 1,4-phenylendiacetic acid (H(2)PDA) under hydrothermal conditions produce isostructural lanthanide coordination polymers with the empirical formula [Ln(2)(PDA)(3)(H(2)O)] x 2H(2)O. The extended structure of [Ln(2)(PDA)(3)(H(2)O)] x 2H(2)O consists of Ln-COO triple helices cross-linked through the [bond]CH(2)C(6)H(4)CH(2)[bond] spacers of the PDA anions, showing 1D open channels along the crystallographic c axis that accommodate the guest and coordinated water molecules. Evacuation of [Er(2)(PDA)(3)(H(2)O)] x 2H(2)O at room temperature and at 200 degrees C, respectively, generates [Er(2)(PDA)(3)(H(2)O)] and [Er(2)(PDA)(3)], both of which give powder X-ray diffraction patterns consistent with that of [Er(2)(PDA)(3)(H(2)O)] x 2H(2)O. The porosity of [Er(2)(PDA)(3)(H(2)O)] and [Er(2)(PDA)(3)] is further demonstrated by their ability to adsorb water vapor to form [Er(2)(PDA)(3)(H(2)O)] x 2H(2)O quantitatively. Thermogravimetric analyses show that [Er(2)(PDA)(3)] remains stable up to 450 degrees C. The effective pore window size in [Er(2)(PDA)(3)] is estimated at 3.4 A. Gas adsorption measurements indicate that [Er(2)(PDA)(3)] adsorbs CO(2) into its pores and shows nonporous behavior toward Ar or N(2). There is a general correlation between the pore size and the kinetic diameters of the adsorbates (CO(2) = 3.3 A, Ar = 3.40 A, and N(2) = 3.64 A). That the adsorption favors CO(2) over Ar is unprecedented and may arise from the combined differentiations on size and on host-guest interactions.

To identify urine biomarkers predictive of acute kidney injury (AKI) in infants admitted to level 2 and 3 neonatal intensive care units with birth weight2000 g and 5-minute Apgar score ≤ 7.A nested case-control study was performed comparing 8 candidate urine AKI biomarkers in infants with AKI (defined as a rise in serum creatinine of at least 0.3 mg/dL or a serum creatinine elevation ≥ 1.7 mg/dL persisting for 3 days) and 24 infants from the described cohort without AKI. Urine was analyzed for neutrophil gelatinase-associated lipocalin, osteopontin, cystatin C, albumin, β(2) microglobulin, epithelial growth factor, uromodulin (UMOD), and kidney injury molecule 1.Compared with the infants without AKI, those with AKI had higher levels of urine cystatin C (1123 pg/mL [95% CI, 272-4635 pg/mL] vs 90 pg/mL [95% CI, 39-205 pg/mL]; P.004; area under the receiver operating characteristic curve [AUC] = 0.82), lower levels of UMOD (11.0 pg/mL [95% CI, 5.7-21.4 pg/mL] vs 26.2 pg/mL [95% CI, 17.4-39.4 pg/mL]; P.03; AUC = 0.77), and lower levels of epithelial growth factor (6.7 pg/mL [95% CI, 4.0-11.3 pg/mL] vs 17.4 pg/mL [95% CI, 12.7-23.8 pg/mL; P = .003; AUC = 0.82). Although the differences were not statistically significant, levels of urine neutrophil-associated gelatinase lipocalin, kidney injury molecule 1, and osteopontin trended higher in infants with AKI.Urinary biomarkers can predict AKI in neonates admitted to level 2 and 3 neonatal intensive care units.

Summary: Diffuse intrinsic pontine glioma (DIPG) is an aggressive and incurable childhood brain tumor for which new treatments are needed. CBL0137 is an anti-cancer compound developed from quinacrine that targets facilitates chromatin transcription (FACT), a chromatin remodeling complex involved in transcription, replication, and DNA repair. We show that CBL0137 displays profound cytotoxic activity against a panel of patient-derived DIPG cultures by restoring tumor suppressor TP53 and Rb activity. Moreover, in an orthotopic model of DIPG, treatment with CBL0137 significantly extends animal survival. The FACT subunit SPT16 is found to directly interact with H3.3K27M, and treatment with CBL0137 restores both histone H3 acetylation and trimethylation. Combined treatment of CBL0137 with the histone deacetylase inhibitor panobinostat leads to inhibition of the Rb/E2F1 pathway and induction of apoptosis. The combination of CBL0137 and panobinostat significantly prolongs the survival of mice bearing DIPG orthografts, suggesting a potential treatment strategy for DIPG.