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The treatment of proximal humerus fracture dislocations can be challenging given the extensive injury to the proximal humeral anatomy and increased risk of devascularization of the humeral head often seen in these injuries. The purpose of this study is to undertake a systematic review of the literature on the functional outcomes, rate of revision, and short- and long-term complications for proximal humerus fracture dislocations treated with open reduction and internal fixation (ORIF). The PubMed and OVID Embase databases were queried for literature reporting on proximal humerus fracture dislocations treated with ORIF. Data including study design, patient demographics, functional outcomes, and complications were recorded. Twelve studies including 294 patients with Neer type 2-, 3-, or 4-part proximal humerus fracture dislocations met the criteria for inclusion. The mean patient age was 53.4 years (19-89 years) with an average follow-up of 2.9 years (1.15-4.9 years). At the final follow-up, the mean Constant score was 73.2 (52-87.3) and the mean Disabilities of the Arm Shoulder and Hand score was 26.6 (17.5-32). Avascular necrosis was observed in 20.0% (0%-82.3%) and nonunion was observed in 3.0% (0%-7.7%) of patients. Conversion to arthroplasty was observed in 10.7% (5%-20%) and a total reoperation was observed in 35.6% (11.8%-89.1%) of patients in studies explicitly reporting these outcomes. In addition to conversion to arthroplasty, common causes of reoperation were revision ORIF (5.2%) and hardware removal (22.2%). Patients undergoing ORIF for proximal humerus fracture dislocations have reasonable functional outcomes but relatively high avascular necrosis and reoperation rates. This information can be used to counsel patients and set expectations about the potential for further surgeries. [ABSTRACT FROM AUTHOR]

Background: Extended oral antibiotic prophylaxis may decrease rates of prosthetic joint infection (PJI) after total joint arthroplasty (TJA) in patients at high risk for infection. However, the cost-effectiveness of this practice is not clear. In this study, we used a break-even economic model to determine the cost-effectiveness of routine extended oral antibiotic prophylaxis for PJI prevention in high-risk TJA patients.Methods: Baseline PJI rates in high-risk patients, the cost of revision arthroplasty for PJI, and the costs of extended oral antibiotic prophylaxis regimens were obtained from the literature and institutional purchasing records. These variables were incorporated in a break-even economic model to calculate the absolute risk reduction (ARR) in infection rate necessary for extended oral antibiotic prophylaxis to be cost-effective. ARR was used to determine the number needed to treat (NNT).Results: Extended oral antibiotic prophylaxis with Cefadroxil in patients at high risk for PJI was cost-effective at an ARR in baseline infection rate of 0.187% (NNT = 535) and 0.151% (NNT = 662) for TKA and THA, respectively. Cost-effectiveness was preserved with varying costs of antibiotic regimens, PJI treatment costs, and infection rates.Conclusion: The use of extended oral antibiotic prophylaxis may reduce PJI rates in patients at high risk for infection following TJA and appears to be cost-effective. However, the current evidence supporting this practice is limited in quality. The use of extended oral antibiotic prophylaxis should be weighed against the possible development of future antimicrobial resistance, which may change the value proposition. [ABSTRACT FROM AUTHOR]

Background: The use of robotic assistance in arthroplasty is increasing; however, the spectrum of adverse events potentially associated with this technology is unclear. Improved understanding of the causes of adverse events in robotic-assisted arthroplasty can prevent future incidents and enhance patient outcomes.Methods: Adverse event reports to the US Food and Drug Administration Manufacturer and User Facility Device Experience database involving robotic-assisted total hip arthroplasty (THA), total knee arthroplasty (TKA), and partial knee arthroplasty were reviewed to determine causes of malfunction and related patient impact.Results: Overall, 263 adverse event reports were included. The most frequently reported adverse events were unexpected robotic arm movement for TKA (59/204, 28.9%) and retained registration checkpoint for THA (19/44, 43.2%). There were 99 reports of surgical delay with an average delay of 20 minutes (range 1-120). Thirty-one cases reported conversion to manual surgery. In total, 68 patient injuries were reported, 7 of which required surgical reintervention. Femoral notching (12/36, 33.3%) was the most common for TKA and retained registration checkpoint (19/28, 67.9%) was the most common for THA. Although rare, additional reported injuries included femoral, tibial, and acetabular fractures, MCL laceration, additional retained foreign bodies, and an electrical burn.Conclusion: Despite the increasing utilization of robotic-assisted arthroplasty in the United States, numerous adverse events are possible and technical difficulties experienced intraoperatively can result in prolonged surgical delays. The events reported herein seem to indicate that robotic-assisted arthroplasty is generally safe with only a few reported instances of serious complications, the nature of which seems more related to suboptimal surgical technique than technology. Based on our data, the practice of adding registration checkpoints and bone pins to the instrument count of all robotic-assisted TJA cases should be widely implemented to avoid unintended retained foreign objects. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy is a microvascular disease that causes blindness. Using acid sphingomyelinase knockout mice, we reported that ceramide generation is critical for diabetic retinopathy development. Here, in patients with proliferative diabetic retinopathy, we identify vitreous ceramide imbalance with pathologic long-chain C16-ceramides increasing and protective very long-chain C26-ceramides decreasing. C16-ceramides generate pro-inflammatory/pro-apoptotic ceramide-rich platforms on endothelial surfaces. To geo-localize ceramide-rich platforms, we invented a three-dimensional confocal assay and showed that retinopathy-producing cytokines TNFα and IL-1β induce ceramide-rich platform formation on retinal endothelial cells within seconds, with volumes increasing 2-logs, yielding apoptotic death. Anti-ceramide antibodies abolish these events. Furthermore, intravitreal and systemic anti-ceramide antibodies protect from diabetic retinopathy in standardized rodent ischemia reperfusion and streptozotocin models. These data support (1) retinal endothelial ceramide as a diabetic retinopathy treatment target, (2) early-stage therapy of non-proliferative diabetic retinopathy to prevent progression, and (3) systemic diabetic retinopathy treatment; and they characterize diabetic retinopathy as a "ceramidopathy" reversible by anti-ceramide immunotherapy. [Display omitted] • Vitreous C16:0/26:0 ceramide ratio is increased in proliferative diabetic retinopathy • C16-ceramide forms pro-inflammatory and pro-apoptotic ceramide-rich platforms • Cytokines induce ceramide-rich platform formation on retinal endothelial cells • Retinal microvascular injury in diabetes is reversed by anti-ceramide immunotherapy Diabetic metabolic abnormalities cause retinal "ceramidopathy," with sphingolipid imbalance leading to pathological ceramide-rich platform formation on the surface of retinal endothelial cells. Anti-ceramide antibodies targeting ceramide-rich platforms inhibit diabetes-induced endothelial cell apoptosis, dysfunction, and increased permeability. Intravitreal and systemic anti-ceramide immunotherapy reverse retinal microvascular injury in diabetic retinopathy. [ABSTRACT FROM AUTHOR]

Background: Distal femoral replacement (DFR) is a potential treatment option following periprosthetic fracture (PPF) of a total knee arthroplasty (TKA). However, there is limited literature regarding implant survivorship and complication rates. The aim of this study was to examine patient demographics and trends in usage, implant survivorship and modes of failure, and patient mortality following DFR for PPF captured by a national joint replacement registry.Methods: A retrospective registry review was performed using data from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR). In total, 306 DFR were performed for PPF of a known primary TKA. Eighty-five percent of patients were female, and the mean age was 76.4 years. Kaplan-Meier estimates of implant and patient survivorship were performed.Results: The number of DFR performed for PPF has doubled over the past five years. The cumulative percent second revision rate at six years was 12%. The most common indications for revision were infection (37%) and aseptic loosening (33%). Patient survivorship after DFR was 97% and 83% at five and ten years, respectively.Conclusion: A national registry review has identified the increasing prevalence of DFR for PPF after primary TKA and demonstrated implant survivorship of 88% at midterm follow-up. Surgeons may consider DFR as an acceptable and durable treatment option.Level Of Evidence: Level III - Case Series. [ABSTRACT FROM AUTHOR]

Discovering the role duodenal exclusion plays in weight loss and resolution of type 2 diabetes (T2D) may help refine the surgical and nonsurgical treatment of obesity and T2D. To assess changes in glucose homeostasis due to duodenal exclusion using a duodenal-jejunal bypass liner (DJBL) in a nonobese canine model. Academic laboratory setting. An intravenous glucose tolerance test (IVGTT), and a mixed-meal tolerance test (MMTT) at baseline, 1, and 6 weeks post DJBL implantation (I1 and I6, respectively), and 1 and 6 weeks post DJBL removal (R1 and R6, respectively) were done in canines (n = 7) fed a normal chow diet. Placement of the DJBL induced weight loss that was maintained until 4 weeks post removal (R4), despite normal food intake. Total bile acids (TBA) and glucagon-like peptide-1 (GLP-1) during the MMTT were significantly increased at I1 and were associated with increased lactate and free fatty acids. Hypoglycemia counter-regulation was blunted during the IVGTT at I1 and I6, returning to baseline at R1. While there were no changes to insulin sensitivity during the experiment, glucose tolerance was significantly increased following the removal of the DJBL at R1. These data show that in a normoglycemic, nonobese canine model, duodenal exclusion induces energy intake-independent weight loss and negative metabolic effects that are reversed following re-exposure of the small intestine to nutrients. • Duodenal-jejunal bypass liner (DJBL) induced food intake-independent weight loss • Bile acids and GLP-1 increased but not insulin sensitivity • Hypoglycemia counterregulation was impaired during duodenal exclusion • Removal of the DJBL improved measures of glucose homeostasis [ABSTRACT FROM AUTHOR]

Indications for reverse total shoulder arthroplasty (RTSA) have expanded to include primary glenohumeral osteoarthritis (GHOA) with an intact rotator cuff. Limited evidence exists on RTSA in patients with primary GHOA and no posterior glenoid wear (Walch A1, A2, and B1 morphologies). The purpose of this retrospective cohort study was to determine if glenoid morphology is associated with clinical outcomes in patients undergoing RTSA for primary GHOA. A retrospective review of prospectively collected data was performed in patients undergoing primary RTSA for GHOA with a minimum of 2-year clinical follow-up. Preoperative computed tomography and magnetic resonance imaging were used to categorize glenoid morphology as described by the modified Walch classification. Pre- and postoperative American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES), Single Assessment Numeric Evaluation (SANE), visual analog scale (VAS) pain scores, and range of motion (ROM) measurements were compared across Walch glenoid subtypes. The percentage of patients that reached previously established clinically significant thresholds for minimal clinically important difference (MCID) and substantial clinical benefit (SCB) was also comparatively assessed. Multivariable analysis was used to evaluate the association between glenoid morphology and postoperative ASES score while controlling for potentially confounding variables. Of the 247 consecutive patients, 197 were available at a minimum 2-year follow-up (80%). Significant improvements were seen in ASES, VAS pain, SANE, and ROM from baseline to final postoperative follow-up in the combined patient cohort (all P <.001). Most (98.0%) patients reached MCID, and 90.9% of patients reached SCB for ASES threshold. No significant differences were found among Walch subtypes in terms of preoperative to postoperative improvement in ASES (P =.39), SANE (P =.4), VAS pain (P =.49), forward elevation (P =.77), external rotation (P =.45), or internal rotation (P = 0.1). The only significant difference in postoperative outcomes between Walch glenoid subtypes was higher postoperative ASES scores among type B3 glenoids compared with type A1 glenoids (P =.03) on univariate analysis. However, no individual Walch glenoid subtype was associated with lower postoperative ASES scores on multivariable analysis (P >.05). Primary RTSA provides excellent short-term outcomes in patients with glenohumeral arthritis with intact rotator cuff, regardless of the degree of preoperative glenoid deformity. Surgeons can use these data to support the use of RTSA for glenohumeral arthritis in a more standardized way. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jml.2009.10.002 Byline: Ruskin H. Hunt, Richard N. Aslin Keywords: Statistical learning; Category induction; Serial reaction time; Distributional analysis; Artificial grammar Abstract: Category formation lies at the heart of a number of higher-order behaviors, including language. We assessed the ability of human adults to learn, from distributional information alone, categories embedded in a sequence of input stimuli using a serial reaction time task. Artificial grammars generated corpora of input strings containing a predetermined and constrained set of sequential statistics. After training, learners were presented with novel input strings, some of which contained violations of the category membership defined by distributional context. Category induction was assessed by comparing performance on novel and familiar strings. Results indicate that learners develop increasing sensitivity to the category structure present in the input, and become sensitive to fine-grained differences in the pre- and post-element contexts that define category membership. Results suggest that distributional analysis plays a significant role in the development of visuomotor categories, and may play a similar role in the induction of linguistic form-class categories. Author Affiliation: Brain and Cognitive Sciences, University of Rochester, Rochester, NY 14627, United States Article History: Received 28 August 2008; Revised 16 October 2009

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jbusres.2008.03.002 Byline: Zeki Simsek (a), Michael H. Lubatkin (a)(b), John F. Veiga (a), Richard N. Dino (a) Keywords: Corporate entrepreneurship; Entrepreneurial alertness; Information system Abstract: The literature has suggested that an entrepreneurially alert information system may be a salient driver of corporate entrepreneurship, even though this role has been neither theoretically articulated nor empirically substantiated. Building upon the organizational learning, information orientation, and entrepreneurial awareness literatures we identify three key elements of a firm's entrepreneurially alert information system, and then develop a parsimonious model that examines the impact of these elements on corporate entrepreneurship. Using both single- and multi-source survey data from 495 small- to medium-sized firms, we test our model and find that each element individually and collectively imparts significant positive influence on corporate entrepreneurship. Author Affiliation: (a) University of Connecticut, School of Business, Management Department, 2100 Hillside Road Unit 1041; Storrs, CT 06269-1041, United States (b) EM Lyon, France Article History: Received 13 September 2006; Accepted 5 March 2008

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jml.2008.07.002 Byline: Bob McMurray (a), Michael K. Tanenhaus (b), Richard N. Aslin (b) Keywords: Spoken word recognition; Speech perception; Gradiency; Eye movements; Lexical ambiguity; Attractor dynamics; Phoneme categorization; TRACE model of word recognition; Mismatch Abstract: Spoken word recognition shows gradient sensitivity to within-category voice onset time (VOT), as predicted by several current models of spoken word recognition, including TRACE (McClelland, J., & Elman, J. (1986). The TRACE model of speech perception. Cognitive Psychology, 18, 1-86). It remains unclear, however, whether this sensitivity is short-lived or whether it persists over multiple syllables. VOT continua were synthesized for pairs of words like barricade and parakeet, which differ in the voicing of their initial phoneme, but otherwise overlap for at least four phonemes, creating an opportunity for 'lexical garden-paths' when listeners encounter the phonemic information consistent with only one member of the pair. Simulations established that phoneme-level inhibition in TRACE eliminates sensitivity to VOT too rapidly to influence recovery. However, in two Visual World experiments, look-contingent and response-contingent analyses demonstrated effects of word initial VOT on lexical garden-path recovery. These results are inconsistent with inhibition at the phoneme level and support models of spoken word recognition in which sub-phonetic detail is preserved throughout the processing system. Author Affiliation: (a) Department of Psychology, E11 SSH, University of Iowa, Iowa City, IA 52240, USA (b) Department of Brain and Cognitive Sciences, University of Rochester, USA Article History: Received 5 December 2007; Revised 4 July 2008

People are increasingly turning to online search engines for health information. We analyzed Google search queries to determine the most frequently asked topics and questions related to shoulder arthroplasty and the sources of the websites provided to address these questions. Search terms for shoulder arthroplasty were entered into Google. Machine learning–based natural language processing algorithms within Google were used to mine search logs to identify frequently asked questions about shoulder arthroplasty. These questions with their associated websites were extracted and categorized by two independent reviewers. A total of 300 questions were extracted with 156 associated websites. The most popular question topics were related to the timeline of recovery (16.3%), ability to perform specific activities (15.7%), technical details of surgery (14.3%), and activity restrictions (12%). Frequently asked questions had to do with the fastest means of recovery, duration of physical therapy, sling use, time spent sleeping upright in a recliner, time off work, location of surgical incision, resumption of sports, and the ability to use the bathroom. The most common websites provided to address the questions were academic (25.3%), private practice (23%), and government (20.3%). The most frequently asked questions on Google about shoulder arthroplasty centered around postoperative rehabilitation and restrictions, with information originating from variable sources. Our data can be used to counsel patients and set expectations about recovery and serve as a framework for the development of targeted patient education materials. Level VI; Descriptive Study [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jhg.2007.11.002 Byline: Richard N. Schofield Abstract: Mixed international commissions have been centrally involved in shaping the outer margins of the state territory of Iraq over the last century and a half. Laborious Anglo-Russian efforts to narrow the traditional Perso-Ottoman frontier in the seventy-year period before the Great War contrasted with the League of Nations' ostensibly speedy treatment of Iraq's more arbitrary northern and north-western territorial limits in the early inter-war years. Most recently, a team appointed by the UN Secretary-General finalised definition of Iraq's international boundaries with Kuwait when the emirate was liberated from Iraqi occupation in the spring of 1991. This article scrutinises the role played by these bodies in the boundary evolutionary process from a review of their primary records. It highlights the fact that the evolution of Iraq's (and those of its Ottoman forbears) international boundaries to the east, north and west was rarely straightforward and reflected both regional considerations and imperial contexts. The problem of reconciling inadequate textual definitions with features on the ground has been a constant phenomenon. Deciding whether commissions actually delimited or demarcated territory was as valid a question following the UN's Iraq-Kuwait settlement as in the mid-nineteenth century. Whether many historical treaty delimitations were ever designed to be anything more than territorial allocations is another theme explored in this article. Author Affiliation: Department of Geography, King's College London, Strand, London WC2R 2LS, UK

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2006.12.011 Byline: Ekaterina Voronina (a), Lindsay A. Lovasco (a), Aron Gyuris (a), Robert A. Baumgartner (a), Albert F. Parlow (b), Richard N. Freiman (a) Keywords: Folliculogenesis; Granulosa cells; TAF4b; TFIID; Survival; Proliferation; Atresia Abstract: Oocyte development in the mammalian ovary requires productive interactions with somatic granulosa cells of the ovarian follicle. Proliferating granulosa cells support the progression of follicular growth and maturation, multiplying dramatically as it unfolds. The cell cycle recruitment of granulosa cells is regulated at least in part by hormones such as follicle-stimulating hormone (FSH) and estrogen. Follicles recruited into the growth phase following formation of multiple layers of granulosa cells have two major fates: either to continue proliferation followed by differentiation, or to die by programmed cell death, or atresia. While many of the signaling pathways orchestrating ovarian follicle development are known, the downstream transcriptional regulators that integrate such signals in the mammalian ovary remain to be defined. Recent experiments in diverse organisms have revealed multiple instances of gonad-selective components of the basal transcriptional machinery. One such protein, TAF4b, is a gonadal-enriched coactivator subunit of the TFIID complex required for normal female fertility in the mouse. To determine the etiology of female infertility of the TAF4b-deficient mice, we have determined multiple functions of TAF4b during postnatal ovarian follicle development. Here we demonstrate that the TAF4b protein is expressed in the granulosa cell compartment of the mammalian ovarian follicle. Furthermore, TAF4b-deficient mouse ovaries contain reduced numbers of primordial as well as growing follicles and a concomitant increased proportion of apoptotic follicles in comparison to wild type counterparts. Importantly, TAF4b-null follicles are largely resistant to induction of proliferation in response to multiple hormonal stimuli including estrogen and FSH and demonstrate compromised granulosa cell survival. Together, these data suggest that TAF4b integrates a program of granulosa cell gene expression required for normal ovarian follicle survival and proliferation in response to diverse ovarian signaling events. Author Affiliation: (a) Brown University, Department of Molecular and Cell Biology and Biochemistry, 69 Brown St., Box G-J115, Providence, RI 02912, USA (b) National Hormone and Peptide Program, Harbor-UCLA Medical Center, 1000 W. Carson. St., Torrance, CA 90509, USA Article History: Received 25 July 2006; Revised 27 November 2006; Accepted 6 December 2006

Byline: Daniel Swingley (a), Richard N. Aslin (b) Keywords: Word learning; Language acquisition; Phonology; Categorization; Child development Abstract: In two experiments, 1.5-year-olds were taught novel words whose sound patterns were phonologically similar to familiar words (novel neighbors) or were not (novel nonneighbors). Learning was tested using a picture-fixation task. In both experiments, children learned the novel nonneighbors but not the novel neighbors. In addition, exposure to the novel neighbors impaired recognition performance on familiar neighbors. Finally, children did not spontaneously use phonological differences to infer that a novel word referred to a novel object. Thus, lexical competition -- inhibitory interaction among words in speech comprehension -- can prevent children from using their full phonological sensitivity in judging words as novel. These results suggest that word learning in young children, as in adults, relies not only on the discrimination and identification of phonetic categories, but also on evaluating the likelihood that an utterance conveys a new word. Author Affiliation: (a) Department of Psychology, University of Pennsylvania, 3401 Walnut St. 302C, Philadelphia, PA 19104, USA (b) Department of Brain and Cognitive Sciences, Meliora Hall, University of Rochester, Rochester, NY 14627, USA Article History: Accepted 17 May 2006

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jpolmod.2006.06.007 Byline: Richard N. Cooper Keywords: US current account deficit; Savings rate; Chinese currency; Global imbalances Abstract: This paper questions three separate but related contentions: that Americans save too little; that the large US current account deficit is unsustainable; and that the Chinese currency (rmb) requires large appreciation. Viewed from the perspective of a knowledge-based economy in a globalized world undergoing dramatic demographic change, Americans save quite enough for the future and the US current account deficit is a natural and indeed an expected phenomenon. It can persist for many years. The current configuration of surpluses and deficits is mutually beneficial so long as Americans continue to invest productively. A significant revaluation of the rmb would yield little benefit and would run a grave risk of precipitating financial crises. Author Affiliation: Department of Economics, Harvard University, Cambridge, MA 02138-3016, USA

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.chb.2004.06.001 Byline: Richard N. Landers, John W. Lounsbury Keywords: Big five; Broad and narrow traits; Internet usage; Work drive; Optimism; Tough-mindedness Abstract: The relationship between Internet usage and the Big Five as well as three narrow personality traits was examined using 117 undergraduates as study participants. Results indicated that total Internet usage was negatively related to three of the Big Five traits - Agreeableness, Conscientiousness, and Extraversion as well as two narrow traits - Optimism and Work Drive, and positively related to Tough-Mindedness. The results of a hierarchical regression analysis indicated that Work Drive added significantly to Extraversion and Conscientious in the prediction of total Internet usage, producing a multiple correlation of 0.349 (p Author Affiliation: Department of Psychology, University of Tennessee, Knoxville, TN 37996 0900, USA

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jml.2005.09.003 Byline: Sarah C. Creel, Richard N. Aslin, Michael K. Tanenhaus Keywords: Artificial lexicon; Lexical learning; Lexical acquisition; Consonant; Vowel; Word learning; Lexical activation Abstract: The role of segment similarity in early (i.e., partially learned) lexical entries was assessed using artificial lexicons in a referential context. During a learning phase participants heard 40 nonsense words, each accompanied by an unfamiliar picture. In testing, participants heard the direction 'Click on the [X]', and chose which of four pictures was the target (X). Target lexical items (e.g., pibo) appeared with foils that were similar: cohort items (pib u), rhymes (d ibo), matched consonants (p a b u) or matched vowels (d i k o). Two initial experiments demonstrated cohort and rhyme confusions, similar to lexical activation findings. Four further experiments explored the role of segment similarity in word confusions. Consonant-matched CVCV stimuli were more strongly confused with each other than were vowel-matched CVCV stimuli. Placing consonants in syllable-final position (VC[f]VC) weakened consonant effects and strengthened vowel effects. These results suggest that syllable-initial segments play a strong role in word similarity and constrain the organization of new lexical items. Author Affiliation: Department of Brain and Cognitive Sciences, Meliora Hall, University of Rochester, Rochester, NY 14627, USA Article History: Received 20 December 2004; Revised 19 September 2005

Titan, the largest satellite of Saturn, has a thick nitrogen/methane atmosphere with a thick global organic haze. A laboratory analogue of Titan's haze, called tholin, was formed in an inductively coupled plasma from nitrogen/methane = 90/10 gas mixture at various pressures ranging from 13 to 2300 Pa. Chemical and optical properties of the resulting tholin depend on the deposition pressure in cold plasma. Structural analyses by IR and UV/VIS spectroscopy, microprobe laser desorption/ionization mass spectrometry, and Raman spectroscopy suggest that larger amounts of aromatic ring structures with larger cluster size are formed at lower pressures (13 and 26 Pa) than at higher pressures (160 and 2300 Pa). Nitrogen is more likely to incorporate into carbon networks in tholins formed at lower pressures, while nitrogen is bonded as terminal groups at higher pressures. Elemental analysis reveals that the carbon/nitrogen ratio in tholins increases from 1.5-2 at lower pressures to 3 at 2300 Pa. The increase in the aromatic compounds and the decrease in C/N ratio in tholin formed at low pressures indicate the presence of the nitrogen-containing polycyclic aromatic compounds in tholin formed at low pressures. Tholin formed at high pressure (2300 Pa) consists of a polymer-like branched chain structure terminated with -C[H.sub.3], -N[H.sub.2], and -C[equivalent to]N with few aromatic compounds. Reddish-brown tholin films formed at low pressures (13-26 Pa) shows stronger absorptions (almost 10 times larger k-value) in the UV/VIS range than the yellowish tholin films formed at high pressures (160 and 2300 Pa). The tholins formed at low pressures may be better representations of Titan's haze than those formed at high pressures, because the optical properties of tholin formed at low pressures agree well with that of Khare et al. (1984a, Icarus 60, 127-137), which have been shown to account for Titan's observed geometric albedo. Thus, the nitrogen-containing polycyclic aromatic compounds we find in tholin formed at low pressure may be present in Titan's haze. These aromatic compounds may have a significant influence on the thermal structure and complex organic chemistry in Titan's atmosphere, because they are efficient absorbers of UV radiation and efficient charge exchange intermediaries. Our results also indicate that the haze layers at various altitudes might have different chemical and optical properties. Keywords: Titan; Haze; Tholin; Spectroscopy; Organic chemistry; Nitrogen-containing polycyclic aromatic compounds

To reach balance and harmony, current demand, growth, and sustainability, there is a need to include economic, social, cultural, and biological principles for a holistic approach in fisheries management. However, despite the combined efforts, severe challenges still threaten the sustainability of small-scale fisheries in the Philippines. This study carried out a systematic review of the literature published from 1998 to 2021 in the Philippines. This timeframe was selected to align with the implementation of the Philippines Fisheries Code of 1998 (Republic Act 8550) and its subsequent amendment as Republic Act 10654 in 2015, which legally recognized sustainable fisheries by local governments from 1998 onwards. The literature search came out with a total of 775 articles from Web of Science and 345 from SCOPUS, after duplicates were removed, 207 literature were included in the synthesis. The main issues that came out are on fishing, reef, livelihood, catch and protected areas. In the Philippines, the reliance of fishers on their livelihood remains a limiting factor in the effectiveness of management plans as pressure from the increasing population of highly fishery-dependent coastal communities, food insecurity, and catch demand can render tactics ineffective. The root issues are larger and systemic, but stem from a lack of sustainable financing to support the viability of established fishery management schemes. Marine conservation programs require consideration of the economic impacts and creating alternatives to diversify income sources so that other larger drivers of unsustainable fisheries can be addressed. [ABSTRACT FROM AUTHOR]