We study the information rates of unipolar orthogonal frequency division multiplexing (OFDM) in discrete-time optical intensity channels (OIC) with Gaussian noise under average optical power constraint. Several single-, double-, and multicomponent unipolar OFDM schemes are considered under the assumption that independent and identically distributed (i.i.d.) Gaussian or complex Gaussian codebook...

Two new cyclic pentapeptides (1 and 2) and the known blazein (3), ganodesterone (4), ergosterin (5), cerevisterol (6), 24-methylcholesta-4,6,8(14),22-tetraen-3-one (7), 5,8-epidioxyergosta-6,22-dien-3-ol (8), 16-α-d-mannopyranosyloxyisopimar-7-en-19-oic acid (9), and 16-hydroxy isopimar-7-en-19-oic acid (10) have been isolated from the crude extract of an endolichenic Xylaria sp. The structures...

Two new ursane-type triterpenoids, 3β,19α,23-trihydroxyurs-12-en-24-al-28-oic acid (1) and 3β,19α,24-trihydroxy-23-norurs-12-en-28-oic acid (2), two new pregnane derivatives, 3β,12β-dihydroxy-5α-pregnane-14,16-dien-20-one (9) and 12β-hydroxy-5α-pregnane-14,16-dien-3,20-dione (10), and eight known compounds were isolated from the twigs and leaves of Emmenopterys henryi. The structures of the new...

An efficient methodology for the preparation of the α-tetrasubstituted proline analog (S,S,S)-2-methyloctahydroindole-2-carboxylic acid, (S,S,S)-(αMe)Oic, and its enantiomer, (R,R,R)-(αMe)Oic, has been developed. Starting from easily available substrates and through simple transformations, a racemic precursor has been synthesized in excellent yield and further subjected to HPLC resolution using...

Naloxegol is a polyethylene glycol derivative of naloxone approved in the US as a once-daily oral treatment for opioid-induced constipation (OIC) in adults with chronic noncancer pain. Population exposure-response models were constructed based on data from two phase III studies comprising 1,331 adults with noncancer pain and OIC. In order to characterize the protocol-defined naloxegol responder...

Three new ursane triterpenes, 3α,19α-dihydroxy-2-nor-urs-12-en-23,28-dioic acid-23-methyl ester (1), 19α,23-dihydroxy-3-oxo-2-nor-urs-12-en-28-oic acid (2), and 2,3-seco-3-methoxy-3,19α,23-trihydroxy-urs-12-en-2-al-28-oic acid (3), were isolated from the MeOH extract of the branch barks of Davidia involucrata, together with six known compounds. Their structures were elucidated by means of vario...

The title compound, C(30)H(48)O(3), a triterpene isolated from the resin of canarium schweinfurthiiand, is an isomer of the previously reported triterpene 3α-hy-droxy-tirucalla-7,24-dien-21-oic acid [Mora et al. (2001 ▶). Acta Cryst. C57, 638-640], which crystallizes in the same trigonal space group. The title mol-ecule consists of four fused rings having chair, half-chair, half-chair and envel...

We present a theory of why some countries negotiate trade agreements during economic downturns. We argue that political leaders can gain from such agreements because of the signals they send to their publics. Publics are less likely to blame leaders for bad economic conditions when they have implemented sound economic policies, such as signing and implementing agreements designed to liberalize ...

Background Opioid-induced constipation (OIC) has become more common in the intensive care unit (ICU) due to increased opioid utilization. Traditional laxatives often prove ineffective against OIC, leading utilization of naloxegol. However, further research is needed confirm naloxegol's effectiveness and safety critical care. This study aimed explore efficacy this intervention critically ill OIC...