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Baffin Bay is the travel destination of most icebergs calving from west Greenland. They commonly follow the bay's cyclonic circulation and might end up far south along the coast of Newfoundland and Labrador, where many shipping routes converge. Given the hazard that icebergs pose to marine transportation, understanding their distribution is fundamental. One of the forces driving iceberg drift arises from the presence of sea ice. Observations in the Southern Ocean indicate that icebergs get locked in thick and concentrated sea ice. We present observations that support the occurrence of this sea ice locking mechanism (SIL) in Baffin Bay as well. Most iceberg models, however, represent the sea ice force over an iceberg as a simple drag force. Here, we implement a new parameterization in the iceberg module of the Nucleus for European Modeling of the Ocean (NEMO‐ICB) to represent SIL. We show that, by using this new parameterization, icebergs are more likely to travel outside of the Baffin Island Current during winter, which is supported by satellite observations. There is a slight improvement in the representation of iceberg severity along the coast of Newfoundland and Labrador and a slight shift of iceberg melt toward this region and Lancaster Sound/Hudson Strait. Although the impacts of icebergs on sea ice are still not represented, and targeted observations are needed for model calibration regarding sea ice concentration thresholds from which icebergs get locked, we are confident that this model improvement takes iceberg modeling one step forward toward reality. Plain Language Summary: After they break off Greenland's glaciers, icebergs drift in the ocean in somewhat predictable patterns across Baffin Bay. What makes them predictable is that we know the main natural forces that cause icebergs to move: the winds, the ocean currents, and the sea ice cover. Because it is impossible to monitor all the icebergs coming from Greenland, we use computer models to understand their typical trajectories. In these models, each one of the forces responsible for iceberg drift can be represented mathematically, usually in a very simplistic way. The sea ice force, for example, is proportional to how much friction there is between the iceberg and sea ice. However, observations in nature show that the iceberg‐sea ice interaction is more complicated than that: if the sea ice cover is thick and compact, it is able to trap icebergs, and both will move as one solid block. In this study, we improve a model's representation of the sea ice force by including this trapping mechanism. Results show that iceberg trajectory can be slightly different during winter due to sea ice trapping and that this mechanism potentially improves our ability to predict when icebergs reach the transatlantic shipping routes east of Canada. Key Points: A new sea ice‐iceberg locking parameterization was implemented in Nucleus for European Modeling of the Ocean and tested in a 1/4° resolution regional configurationIcebergs locked in sea ice in Baffin Bay are more likely to travel outside of the Baffin Island Current than "unlocked" onesThe existence of a sea ice locking mechanism in Baffin Bay is supported by observations of co‐varying iceberg and sea ice speeds [ABSTRACT FROM AUTHOR]

Since 21 000 yr ago, the oceans have received large amounts of freshwater in pulses coming from the melting ice sheets. A specific event, known as meltwater pulse 1A (MWP-1A), has been identified in sea-level and temperature proxy records as responsible for the increase of _20m in sea level in less than 500 yr. Although its origin and timing are still under discussion, MWP-1A seems to have had a significant impact on several components of the climatic system. The present work aims to elucidate these impacts on the water mass distribution of the South Atlantic Ocean through the analysis of a transient simulation of the climate evolution from the Last Glacial Maximum to Present Day using a state-of-art CGCM, the National Center for Atmospheric Research Community Climate System Model version 3 (NCAR CCSM3). Results show that the freshwater discharge associated with the timing of MWP-1A was crucial to establish the present thermohaline structure associated with the North Atlantic Deep Water, marking the transition between a shallower and a deeper Atlantic Meridional Overturning Circulation. [ABSTRACT FROM AUTHOR]

Soil as mineral impurity in sugarcane loads impacts the Brazilian sugar-ethanol industry with rising production and maintenance costs as well as decreased productivity. The mechanical harvesting of sugarcane was conceived as a technology with potential to increase the raw material quality thereby has been gradually replacing manual harvesting throughout the country. Instrumental neutron activation analysis was applied for determination of soil tracers in order to compare the performance of both harvesting systems in terms of mineral impurities. There were no significant differences in the amount of soil transported to sugarcane industry despite the technological progress aggregated to mechanical harvesting. However, for both harvesting systems there were significant differences on the amount of such mineral impurity between clay and sandy soils. [ABSTRACT FROM AUTHOR]

Background: Acne vulgaris is a complex, multifactorial, inflammatory skin condition. Although frequently presented at dermatology clinics, the literature on adult acne is scarce, particularly concerning skin barrier function and management. We aimed to provide insights into the role of skin barrier integrity in adult acne patients and the role of cleansers and moisturizers as adjunctive to treating and maintaining adult acne.   Methods: A panel of eight dermatologists who treat adult patients with acne developed a consensus paper on the role of skin barrier function and skin care in adult acne management. The modified Delphi method comprised a face-to-face meeting and online follow-up to discuss the results of a scoping literature review. Drawing from their experience and opinions, they agreed on seven consensus statements.   Results: Epidermal barrier dysfunction plays a vital role in acne pathogenesis and asymmetrically impacts adult female acne. Erythema, pruritus, peeling, and xerosis are common adverse effects of first-line acne treatment options and, if not appropriately counseled and managed, can exacerbate, leading to regimen nonadherence and poor patient experience and outcomes., Conclusion: Improving patient knowledge of comprehensive acne treatments, including quality adjunctive cleansers and moisturizers, may maximize regimen efficacy and provide patients with personalized and successful acne treatment and maintenance tools. J Drugs Dermatol. 2024;23(8):674-679.     doi:10.36849/JDD.8471.

Home-based photobiomodulation is a popular treatment modality for patients seeking non-invasive aesthetic treatment. Studies demonstrate that photobiomodulation is effective for skin rejuvenation, which is aimed at improving the overall appearance of the skin by reducing fine lines and wrinkles and improving skin texture, skin tone, and dyspigmentation. Most current skin rejuvenation research focuses on treatments in women. However, men's aesthetics remains an underserved market. A combined red light (RL) and near-infrared (NIR) light-emitting diode (LED) has been designed specifically to target male skin, which may have different physiological and biophysical properties compared to female skin. Herein, the safety and efficacy of a commercially available RL and NIR (633, 830, and 1072 nm) LED array designed to be worn as a face mask was assessed. Primary outcomes included adverse events and facial rejuvenation as determined by participant-reported satisfaction scales and quantitative digital skin photography and computer analysis after 6 weeks of treatment. The participants reported overall favorable results and improvements in all individual categories, were satisfied with the treatment, and would recommend the product to others. The participants perceived the greatest improvement in fine lines and wrinkles, skin texture, and youthful appearance. Photographic digital analysis demonstrated favorable improvements in wrinkles, UV spots, brown spots, pores, and porphyrins. These results support the use of RL and NIR to treat male skin. Advantages of the LED facemask include its safety, efficacy, convenient home-based use, minimal associated downtime, simple operation, non-invasiveness, and appreciable results in as few as 6 weeks., (© 2023. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Background: Dysregulation of either the cutaneous microbiome (CM) or epidermal barrier function (EBF) is thought to play an increasingly important role in acne vulgaris (AV) and rosacea pathogenesis., Objective: To review the literature regarding epidermal barrier dysfunction (EBD) and cutaneous dysbiosis in AV and rosacea and provide clinical pearls for dermatologists., Methods: A Medline literature search was performed for relevant literature regarding EBD and dysbiosis and either AV or rosacea. An expert consensus panel was then convened to discuss article merits and distill findings into clinical pearls., Results: Final review included 138 articles. Puberty may alter natural stratum corneum lipid ratios, instigating and/or exacerbating EBD in AV. Patients with severe AV have an abundance of virulent Cutibacterium acnes phylotype IA1. EBD may manifest as classic signs of rosacea and improve with treatment. While several microbial populations are dysregulated in rosacea, the effect from any singular species is unclear. Current AV and rosacea treatment regimens may mitigate inflammation but may also indiscriminately damage CM and EBF. Physiologic moisturizers and cleansers that harness pre-/pro-/postbiotics may have a role in restoring CM, EBF, and potentially improving dermatosis severity., Limitations: Limited prospective clinical trial data especially regarding over-the-counter (OTC)/non-prescription skincare products., Conclusion: Appropriately developed prescription and OTC preparations may selectively influence the microbiome and potentially maintain/restore EBF. By understanding this relationship, dermatologists will be better able to educate patients on the importance of appropriate skin care.J Drugs Dermatol. 2022;21:9(Suppl 2):s5-14.

Circulating immunoreactive inhibin concentrations were determined in male chimpanzees (n = 12) during a 36-mo period starting 18 mo before the onset of pubertal testicular growth (Po). Serum levels of inhibin started to increase, together with LH and testosterone, 6 mo before a rise in FSH and Po. Before Po, inhibin was not related to gonadotropins but was related to testosterone levels (r = 0.263; p < 0.005; R2 = 7%). After Po, inhibin remained related to testosterone (r = 0.289, p < 0.01) but became inversely related to gonadotropins; FSH was the best predictor (r = -0.382, p < 0.0005; R2 = 30%) of this relationship. During the progressive rise in circulating inhibin, FSH increased and plateaued during 9 mo, then dropped to prepubertal levels. These findings suggest that a specific closed-loop negative feedback system for the secretion of FSH by inhibin is not functional before the onset of puberty in the chimpanzee. This feedback system seems to fully operate several months after the LH rise and may be related to the complete maturation of both Sertoli cells and spermatogenesis.

Cellular and biochemical characteristics of semen obtained by masturbation were studied in 5 pubertal chimpanzees during 1.5 yr. The dental age corresponding to the beginning of the pubertal testicular growth (Po) ranged from 5.0 to 8.3 years (mean = 6.7 +/- 1.2 yr). Time-related variations of all studied parameters were analyzed according to Po and, therefore, independently of the dental age. The emission of first ejaculates, and therefore the onset of activity of the accessory sex gland, was estimated to occur 4 mo after Po. The ejaculate volume (n = 132, r = 0.704, p less than 0.001), as well as the total amounts of l-carnitine (n = 65, r = 0.649, p less than 0.001), fructose (r = 0.522, p less than 0.001), citrate (r = 0.748, p less than 0.001), and acid phosphatase (r = 0.756, p less than 0.001) increased with time. First-obtained ejaculates contained no spermatozoa. Spermarche was estimated to occur 9.4 mo after Po. Total sperm count increased with time (r = 0.595, p less than 0.001). The motility and viability of spermatozoa increased with time (r = 0.474, p less than 0.01 and r = 0.632, p less than 0.001, respectively) while their morphology did not vary. The volume of the liquefied fraction and its content in free spermatozoa considered as available for fecundation remained low until the end of the study, most likely because of a delayed maturation of the prostate. This study shows that the maturation of the male genital tract is a progressive process. (ABSTRACT TRUNCATED AT 250 WORDS)

The onset of pubertal testicular growth (Po) occurred in 12 out of 20 male chimpanzees surveyed monthly for at least 3.7 yr. When animals were synchronized according to Po, the mean weight gain was found to be higher before than after Po, and testicular volume started to rise immediately after Po. The earlier significant hormonal events were a rapid rise in LH and a slight testosterone increase occurring 6 mo before Po. Thereafter, the levels of LH remained elevated while testosterone continued to rise in parallel with the testicular volume. FSH levels increased suddenly at Po, 6 mo after the LH increase. FSH remained elevated for only 9 mo, then dropped to prepubertal levels. The dissociation between onsets of pubertal increases in LH and FSH secretions suggests that the complete reawakening of the hypothalamic-pituitary unit lasts several months. The secondary drop of FSH, occurring at the time of spermarche, may be induced by factor(s) secreted by the testis.

Unlabelled: Consumption of alcohol and tranquilizers reaches a very high level in France. Studies about simultaneous alcohol and psychotropic drugs involvement in motor related fatalities have never been described in this country. A retrospective study was done on 482 fatalities broken down by drivers and pedestrians within one year (1987) in Région Nord-Pas de Calais (France)., Method: 132 cases met the criteria for complete study. Blood samples obtained at the time of death were analysed for alcohol (BAC) by gas-chromatography and assayed for barbiturates (BA), benzodiazepines (BE) and tricyclic antidepressants (TA) by Emit., Results: Out of 132 fatalities there were 86% men (mean age 38.5 years) and 14% women (mean age 46 years). 57% belonged to the working population. Of the fatalities, 38% occurred from Friday 8 p.m. to Sunday 12 p.m. We distinguished 3 categories: pedestrians (18.2%), 2-wheel vehicles (19%) and 4-wheel vehicles (62.8%). Alcohol involvement is given in Table 2. [table: see text] Notice that 53% were above the legal limit (0.8 g/l) and 34.8% had no alcohol. Psychotropic drugs were detected in 10.6% of the cases (Table 3). [table: see text] BZ were found in 50% of men and 100% of women. drugs and alcohol were present simultaneously in 8.3% of the individuals. Results are in % of total in Table 4: [table: see text] Positive BAC and positive drugs are not related. No significant difference was found in the distribution of alcohol between positive or negative drugs findings. Our results are consistent with those described by North-American authors, but largely superior to those from French or other studies done only on injured persons.

Six men requesting male contraception received a daily oral dose of 20 mg medroxyprogesterone acetate (MPA) in combination with 50 or 100 mg percutaneous testosterone for 1 year. From the third month the sperm concentration was less than 10(6)/ml for all the men at one time or another during treatment, and usually less than 5 X 10(6)/ml, with an average reduction of 95% with respect to pre-treatment values. The sperm count returned to previous values 3-6 months after cessation of the treatment. While FSH and LH secretion was inhibited throughout the treatment period, plasma testosterone levels were not reduced. Oestradiol levels were unaffected while dihydrotestosterone was elevated. The secretory activity of the prostate and seminal vesicles was not appreciably affected; seminal carnitine concentration was reduced during the treatment with a subsequent return to pretreatment values. No pregnancies occurred during treatment. There was no impairment of libido in the subjects, nor any incidence of gynaecomastia, or increase in average body weight. The only observed metabolic side-effect was a moderate increase in glycaemia. A synergistic action of MPA and testosterone is proposed to explain the inhibition of gonadotrophin secretion.

Semen characteristics were studied in 6 wild-born chimpanzees with dental ages ranging approximately from 6 to 12 years. The animals formed 2 groups, early pubertal (EP, N = 3, 6-9 years) and late pubertal (LP, N = 3, 11-12 years). Mean body weight, testicular volume and serum androgen concentration were significantly lower in Group EP (32.2 +/- 1.6 kg, 34.0 +/- 7.7 cm3, 2.1 +/- 0.1 ng/ml) than in Group LP (55.7 +/- 5.7 kg, P less than 0.01; 100.5 +/- 11.9 cm3, P less than 0.01; 3.6 +/- 0.7 ng/ml, P less than 0.05). Ejaculates were obtained by masturbation in all subjects. The mean ejaculate volume was lower in Group EP (0.56 +/- 0.20 ml) than in Group LP (3.77 +/- 0.73 ml, P less than 0.01). In Group EP, 2 animals were azoospermic while the third produced semen with means of 57.1 x 10(6) spermatozoa per ml, 20% motility and 40% vitality. These values were low when compared with the mean values of Group LP (376 x 10(6) spermatozoa per ml, 67% motility and 78% vitality). Mean total sperm count was correlated with testicular volume (r = 0.84) and serum androgen concentration (r = 0.96). The mean concentrations of L-carnitine, fructose, citrate and acid phosphatase for the two groups were not significantly different; but, related to the differences in ejaculate volumes, their total amounts in total ejaculate were lower in Group EP than in Group LP. These results suggest that, in chimpanzees, mechanisms of seminal plasma production and ejaculation are functional early in the reproductive life and that the emission of spermatozoa occurs later.

Semen samples were obtained by masturbation from 6 chimpanzees and the spontaneously liquefied fraction and the remaining coagulum were studied separately. When semen was collected once or twice a week, large intra-individual variations were observed for all measures. The liquefied fraction represented 26.5 +/- 3.2% (weighted mean +/- s.d.) of the total ejaculate but contained 51.3 +/- 3.8% of all emitted spermatozoa. Fructose concentration was higher in the coagulum than in the liquefied fraction (29.3 +/- 3.0 mumol/ml vs 12.0 +/- 2.7 mumol/ml, P less than 0.001) whereas acid phosphatase was less concentrated in the coagulum than in the liquefied fraction (3.5 +/- 0.3 x 10(3) IU/ml vs 13.0 +/- 0.9 x 10(3) IU/ml, P less than 0.001). L-Carnitine and citrate concentrations did not differ between the two fractions of the ejaculate. When semen collection was repeated every hour for 5 h, the ejaculate volume increased from 2.6 +/- 0.7 to 4.7 +/- 0.6 ml (P less than 0.001), whereas total sperm count decreased from 1278 +/- 872 x 10(6) to 587 +/- 329 x 10(6) (P less than 0.05) between the 1st and the 6th ejaculate. In the spontaneously liquefied fraction, the sperm count decreased from 984 to 369 x 10(6). The 6 successive ejaculates gave a total of 20.2 +/- 7.6 ml and 4278 +/- 2884 x 10(6) spermatozoa. The increase of the ejaculate volume was essentially due to an increase of the volume of the coagulum which closely correlated with total amount of fructose (from seminal vesicles) (r = 0.913, P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

In the epididymal fluid of boars, the concentration of carnitine (nmol/mg protein) began to increase from 20 in the distal caput, then rose progressively to 700 in the distal cauda. By contrast, the carnitine content of spermatozoa only started to increase in the proximal cauda where the concentration of carnitine in the fluid was 200-300 nmol/mg protein then gradually increased in spermatozoa from more distal sites. The increase in the acetylcarnitine content of spermatozoa paralleled that of the carnitine amount and represented 50% of the total carnitine (carnitine + acetylcarnitine). We conclude that the acetylcarnitine content of epididymal spermatozoa may be used as a marker of maturation.

The semen characteristics of 215 fertile men (F = fathers requesting vasectomy) and of 409 infertile men (I) have been analysed under strictly identical conditions. The mean values for volume, sperm concentration, and the percentages of motile, vital and morphologically normal spermatozoa were greater in group F than in I. Seminal variations were much greater in cases of testicular lesions (cryptorchidism, hypotrophy) than in varicocele, although there remains a difference between F and I even after exclusion of all clinical lesions suggesting a role for other factors in the origin of much cases of infertility. Other than in cases of azoospermia, there is no difference in the function of the accessory glands detectable by the assay of seminal biochemical markers: fructose (seminal vesicles) acid phosphatase and citrate (prostate); only L-carnitine (epididymal marker) is elevated in the fertile men, however this difference is only a reflection of the observed difference in sperm concentration in combination with the close correlation between sperm concentration and L-carnitine values.

The level of carnitine and acetylcarnitine in spermatozoa of boar epididymal origin and of human ejaculates was demonstrated. In the epididymal fluid of boars, the concentration of carnitine (nmol/mg protein) began to increase from 20 in the distal caput to rise progressively to 700 in the distal cauda. By contrast, the carnitine content of spermatozoa only started to increase in the proximal cauda where the concentration of carnitine in the fluid was 200-300 nmol/mg protein, then gradually increased in spermatozoa from more distal sites. The increase in the acetylcarnitine content of spermatozoa paralleled that of the carnitine amount, represented 50% of total carnitine (carnitine + acetylcarnitine) and coincided with the acquisition of progressive motility. In two populations of human seminal spermatozoa selected by migration and characterised by a very large difference in their percentage of progressively motile cells, higher carnitine and acetylcarnitine contents (40%) were found in migrated spermatozoa compared to the residual population. These results suggest that accumulation of carnitine and its metabolite may be an important factor in the acquisition and the maintenance of progressive motility. Measurement of acetylcarnitine content of human seminal spermatozoa could be used as a marker of epididymal maturation.